ClickHouse/docs/ru/query_language/functions/other_functions.md

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# Прочие функции
## hostName()
Возвращает строку - имя хоста, на котором эта функция была выполнена. При распределённой обработке запроса, это будет имя хоста удалённого сервера, если функция выполняется на удалённом сервере.
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## FQDN {#fqdn}
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Возвращает полное имя домена.
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**Синтаксис**
```sql
fqdn();
```
Эта функция регистронезависимая.
**Возвращаемое значение**
- Полное имя домена.
Тип: `String`.
**Пример**
Запрос:
```sql
SELECT FQDN();
```
Ответ:
```text
┌─FQDN()──────────────────────────┐
│ clickhouse.ru-central1.internal │
└─────────────────────────────────┘
```
## basename
Извлекает конечную часть строки после последнего слэша или бэкслэша. Функция часто используется для извлечения имени файла из пути.
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
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```sql
basename( expr )
```
**Параметры**
- `expr` — Выражение, возвращающее значение типа [String](../../data_types/string.md). В результирующем значении все бэкслэши должны быть экранированы.
**Возвращаемое значение**
Строка, содержащая:
- Конечную часть строки после последнего слэша или бэкслэша.
Если входная строка содержит путь, заканчивающийся слэшем или бэкслэшем, например, `/` или `с:\`, функция возвращает пустую строку.
- Исходная строка, если нет слэша или бэкслэша.
**Пример**
```sql
SELECT 'some/long/path/to/file' AS a, basename(a)
```
```text
┌─a──────────────────────┬─basename('some\\long\\path\\to\\file')─┐
│ some\long\path\to\file │ file │
└────────────────────────┴────────────────────────────────────────┘
```
```sql
SELECT 'some\\long\\path\\to\\file' AS a, basename(a)
```
```text
┌─a──────────────────────┬─basename('some\\long\\path\\to\\file')─┐
│ some\long\path\to\file │ file │
└────────────────────────┴────────────────────────────────────────┘
```
```sql
SELECT 'some-file-name' AS a, basename(a)
```
```text
┌─a──────────────┬─basename('some-file-name')─┐
│ some-file-name │ some-file-name │
└────────────────┴────────────────────────────┘
```
## visibleWidth(x)
Вычисляет приблизительную ширину при выводе значения в текстовом (tab-separated) виде на консоль.
Функция используется системой для реализации Pretty форматов.
`NULL` представляется как строка, соответствующая отображению `NULL` в форматах `Pretty`.
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```sql
SELECT visibleWidth(NULL)
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
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```text
┌─visibleWidth(NULL)─┐
│ 4 │
└────────────────────┘
```
## toTypeName(x)
Возвращает строку, содержащую имя типа переданного аргумента.
Если на вход функции передать `NULL`, то она вернёт тип `Nullable(Nothing)`, что соответствует внутреннему представлению `NULL` в ClickHouse.
## blockSize() {#function-blocksize}
Получить размер блока.
В ClickHouse выполнение запроса всегда идёт по блокам (наборам кусочков столбцов). Функция позволяет получить размер блока, для которого её вызвали.
## materialize(x)
Превращает константу в полноценный столбец, содержащий только одно значение.
В ClickHouse полноценные столбцы и константы представлены в памяти по-разному. Функции по-разному работают для аргументов-констант и обычных аргументов (выполняется разный код), хотя результат почти всегда должен быть одинаковым. Эта функция предназначена для отладки такого поведения.
## ignore(...)
Принимает любые аргументы, в т.ч. `NULL`, всегда возвращает 0.
При этом, аргумент всё равно вычисляется. Это может использоваться для бенчмарков.
## sleep(seconds)
Спит seconds секунд на каждый блок данных. Можно указать как целое число, так и число с плавающей запятой.
## currentDatabase()
Возвращает имя текущей базы данных.
Эта функция может использоваться в параметрах движка таблицы в запросе CREATE TABLE там, где нужно указать базу данных.
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## currentUser() {#other_function-currentuser}
Возвращает логин текущего пользователя. При распределенном запросе, возвращается имя пользователя, инициировавшего запрос.
```sql
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SELECT currentUser();
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```
Алиас: `user()`, `USER()`.
**Возвращаемые значения**
- Логин текущего пользователя.
- При распределенном запросе — логин пользователя, инициировавшего запрос.
Тип: `String`.
**Пример**
Запрос:
```sql
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SELECT currentUser();
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```
Ответ:
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```text
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┌─currentUser()─┐
│ default │
└───────────────┘
```
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## isFinite(x)
Принимает Float32 или Float64 и возвращает UInt8, равный 1, если аргумент не бесконечный и не NaN, иначе 0.
## isInfinite(x)
Принимает Float32 или Float64 и возвращает UInt8, равный 1, если аргумент бесконечный, иначе 0. Отметим, что в случае NaN возвращается 0.
## isNaN(x)
Принимает Float32 или Float64 и возвращает UInt8, равный 1, если аргумент является NaN, иначе 0.
## hasColumnInTable(\['hostname'\[, 'username'\[, 'password'\]\],\] 'database', 'table', 'column')
Принимает константные строки - имя базы данных, имя таблицы и название столбца. Возвращает константное выражение типа UInt8, равное 1,
если есть столбец, иначе 0. Если задан параметр hostname, проверка будет выполнена на удалённом сервере.
Функция кидает исключение, если таблица не существует.
Для элементов вложенной структуры данных функция проверяет существование столбца. Для самой же вложенной структуры данных функция возвращает 0.
## bar {#function-bar}
Позволяет построить unicode-art диаграмму.
`bar(x, min, max, width)` рисует полосу ширины пропорциональной `(x - min)` и равной `width` символов при `x = max`.
Параметры:
- `x` — Величина для отображения.
- `min, max` — Целочисленные константы, значение должно помещаться в `Int64`.
- `width` — Константа, положительное число, может быть дробным.
Полоса рисуется с точностью до одной восьмой символа.
Пример:
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```sql
SELECT
toHour(EventTime) AS h,
count() AS c,
bar(c, 0, 600000, 20) AS bar
FROM test.hits
GROUP BY h
ORDER BY h ASC
```
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```text
┌──h─┬──────c─┬─bar────────────────┐
│ 0 │ 292907 │ █████████▋ │
│ 1 │ 180563 │ ██████ │
│ 2 │ 114861 │ ███▋ │
│ 3 │ 85069 │ ██▋ │
│ 4 │ 68543 │ ██▎ │
│ 5 │ 78116 │ ██▌ │
│ 6 │ 113474 │ ███▋ │
│ 7 │ 170678 │ █████▋ │
│ 8 │ 278380 │ █████████▎ │
│ 9 │ 391053 │ █████████████ │
│ 10 │ 457681 │ ███████████████▎ │
│ 11 │ 493667 │ ████████████████▍ │
│ 12 │ 509641 │ ████████████████▊ │
│ 13 │ 522947 │ █████████████████▍ │
│ 14 │ 539954 │ █████████████████▊ │
│ 15 │ 528460 │ █████████████████▌ │
│ 16 │ 539201 │ █████████████████▊ │
│ 17 │ 523539 │ █████████████████▍ │
│ 18 │ 506467 │ ████████████████▊ │
│ 19 │ 520915 │ █████████████████▎ │
│ 20 │ 521665 │ █████████████████▍ │
│ 21 │ 542078 │ ██████████████████ │
│ 22 │ 493642 │ ████████████████▍ │
│ 23 │ 400397 │ █████████████▎ │
└────┴────────┴────────────────────┘
```
## transform
Преобразовать значение согласно явно указанному отображению одних элементов на другие.
Имеется два варианта функции:
### transform(x, array_from, array_to, default)
`x` - что преобразовывать.
`array_from` - константный массив значений для преобразования.
`array_to` - константный массив значений, в которые должны быть преобразованы значения из from.
`default` - какое значение использовать, если x не равен ни одному из значений во from.
`array_from` и `array_to` - массивы одинаковых размеров.
Типы:
`transform(T, Array(T), Array(U), U) -> U`
`T` и `U` - могут быть числовыми, строковыми, или Date или DateTime типами.
При этом, где обозначена одна и та же буква (T или U), могут быть, в случае числовых типов, не совпадающие типы, а типы, для которых есть общий тип.
Например, первый аргумент может иметь тип Int64, а второй - Array(UInt16).
Если значение x равно одному из элементов массива array_from, то возвращает соответствующий (такой же по номеру) элемент массива array_to; иначе возвращает default. Если имеется несколько совпадающих элементов в array_from, то возвращает какой-нибудь из соответствующих.
Пример:
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```sql
SELECT
2018-04-23 06:20:21 +00:00
transform(SearchEngineID, [2, 3], ['Yandex', 'Google'], 'Other') AS title,
count() AS c
FROM test.hits
WHERE SearchEngineID != 0
GROUP BY title
ORDER BY c DESC
```
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```text
┌─title─────┬──────c─┐
2018-04-23 06:20:21 +00:00
│ Yandex │ 498635 │
│ Google │ 229872 │
2018-04-23 06:20:21 +00:00
│ Other │ 104472 │
└───────────┴────────┘
```
### transform(x, array_from, array_to)
Отличается от первого варианта отсутствующим аргументом default.
Если значение x равно одному из элементов массива array_from, то возвращает соответствующий (такой же по номеру) элемент массива array_to; иначе возвращает x.
Типы:
`transform(T, Array(T), Array(T)) -> T`
Пример:
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```sql
SELECT
transform(domain(Referer), ['yandex.ru', 'google.ru', 'vk.com'], ['www.yandex', 'example.com']) AS s,
count() AS c
FROM test.hits
GROUP BY domain(Referer)
ORDER BY count() DESC
LIMIT 10
```
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```text
┌─s──────────────┬───────c─┐
│ │ 2906259 │
│ www.yandex │ 867767 │
│ ███████.ru │ 313599 │
│ mail.yandex.ru │ 107147 │
│ ██████.ru │ 100355 │
│ █████████.ru │ 65040 │
│ news.yandex.ru │ 64515 │
│ ██████.net │ 59141 │
│ example.com │ 57316 │
└────────────────┴─────────┘
```
## formatReadableSize(x)
Принимает размер (число байт). Возвращает округленный размер с суффиксом (KiB, MiB и т.д.) в виде строки.
Пример:
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```sql
SELECT
arrayJoin([1, 1024, 1024*1024, 192851925]) AS filesize_bytes,
formatReadableSize(filesize_bytes) AS filesize
```
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```text
┌─filesize_bytes─┬─filesize───┐
│ 1 │ 1.00 B │
│ 1024 │ 1.00 KiB │
│ 1048576 │ 1.00 MiB │
│ 192851925 │ 183.92 MiB │
└────────────────┴────────────┘
```
## least(a, b)
Возвращает наименьшее значение из a и b.
## greatest(a, b)
Возвращает наибольшее значение из a и b.
## uptime()
Возвращает аптайм сервера в секундах.
## version()
Возвращает версию сервера в виде строки.
## rowNumberInBlock {#function-rownumberinblock}
Возвращает порядковый номер строки в блоке данных. Для каждого блока данных нумерация начинается с 0.
## rowNumberInAllBlocks()
Возвращает порядковый номер строки в блоке данных. Функция учитывает только задействованные блоки данных.
2019-11-12 08:01:46 +00:00
## neighbor {#neighbor}
2019-08-13 13:11:24 +00:00
2019-11-12 08:01:46 +00:00
Функция позволяет получить доступ к значению в колонке `column`, находящемуся на смещении `offset` относительно текущей строки. Является частичной реализацией [оконных функций](https://en.wikipedia.org/wiki/SQL_window_function) `LEAD()` и `LAG()`.
2019-08-13 13:11:24 +00:00
2019-11-12 08:01:46 +00:00
**Синтаксис**
```sql
neighbor(column, offset[, default_value])
```
Результат функции зависит от затронутых блоков данных и порядка данных в блоке. Если сделать подзапрос с ORDER BY и вызывать функцию извне подзапроса, можно будет получить ожидаемый результат.
2019-08-13 13:11:24 +00:00
2019-11-12 08:01:46 +00:00
**Параметры**
- `column` — Имя столбца или скалярное выражение.
- `offset` - Смещение от текущей строки `column`. [Int64](../../data_types/int_uint.md).
- `default_value` - Опциональный параметр. Значение, которое будет возвращено, если смещение выходит за пределы блока данных.
**Возвращаемое значение**
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- Значение `column` в смещении от текущей строки, если значение `offset` не выходит за пределы блока.
2019-11-12 08:01:46 +00:00
- Значение по умолчанию для `column`, если значение `offset` выходит за пределы блока данных. Если передан параметр `default_value`, то значение берется из него.
Тип: зависит от данных в `column` или переданного значения по умолчанию в `default_value`.
**Пример**
Запрос:
```sql
SELECT number, neighbor(number, 2) FROM system.numbers LIMIT 10;
```
2019-08-13 13:11:24 +00:00
2019-11-12 08:01:46 +00:00
Ответ:
```text
┌─number─┬─neighbor(number, 2)─┐
│ 0 │ 2 │
│ 1 │ 3 │
│ 2 │ 4 │
│ 3 │ 5 │
│ 4 │ 6 │
│ 5 │ 7 │
│ 6 │ 8 │
│ 7 │ 9 │
│ 8 │ 0 │
│ 9 │ 0 │
└────────┴─────────────────────┘
```
Запрос:
```sql
SELECT number, neighbor(number, 2, 999) FROM system.numbers LIMIT 10;
```
Ответ:
```text
┌─number─┬─neighbor(number, 2, 999)─┐
│ 0 │ 2 │
│ 1 │ 3 │
│ 2 │ 4 │
│ 3 │ 5 │
│ 4 │ 6 │
│ 5 │ 7 │
│ 6 │ 8 │
│ 7 │ 9 │
│ 8 │ 999 │
│ 9 │ 999 │
└────────┴──────────────────────────┘
```
Эта функция может использоваться для оценки year-over-year значение показателя:
Запрос:
2019-08-13 13:11:24 +00:00
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```sql
2019-08-13 13:11:24 +00:00
WITH toDate('2018-01-01') AS start_date
SELECT
toStartOfMonth(start_date + (number * 32)) AS month,
toInt32(month) % 100 AS money,
2019-08-23 01:31:04 +00:00
neighbor(money, -12) AS prev_year,
2019-08-13 13:11:24 +00:00
round(prev_year / money, 2) AS year_over_year
FROM numbers(16)
```
2019-11-12 08:01:46 +00:00
Ответ:
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```text
2019-08-13 13:11:24 +00:00
┌──────month─┬─money─┬─prev_year─┬─year_over_year─┐
│ 2018-01-01 │ 32 │ 0 │ 0 │
│ 2018-02-01 │ 63 │ 0 │ 0 │
│ 2018-03-01 │ 91 │ 0 │ 0 │
│ 2018-04-01 │ 22 │ 0 │ 0 │
│ 2018-05-01 │ 52 │ 0 │ 0 │
│ 2018-06-01 │ 83 │ 0 │ 0 │
│ 2018-07-01 │ 13 │ 0 │ 0 │
│ 2018-08-01 │ 44 │ 0 │ 0 │
│ 2018-09-01 │ 75 │ 0 │ 0 │
│ 2018-10-01 │ 5 │ 0 │ 0 │
│ 2018-11-01 │ 36 │ 0 │ 0 │
│ 2018-12-01 │ 66 │ 0 │ 0 │
│ 2019-01-01 │ 97 │ 32 │ 0.33 │
│ 2019-02-01 │ 28 │ 63 │ 2.25 │
│ 2019-03-01 │ 56 │ 91 │ 1.62 │
│ 2019-04-01 │ 87 │ 22 │ 0.25 │
└────────────┴───────┴───────────┴────────────────┘
```
## runningDifference(x)
Считает разницу между последовательными значениями строк в блоке данных.
Возвращает 0 для первой строки и разницу с предыдущей строкой для каждой последующей строки.
Результат функции зависит от затронутых блоков данных и порядка данных в блоке.
Если сделать подзапрос с ORDER BY и вызывать функцию извне подзапроса, можно будет получить ожидаемый результат.
Пример:
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```sql
SELECT
EventID,
EventTime,
runningDifference(EventTime) AS delta
FROM
(
SELECT
EventID,
EventTime
FROM events
WHERE EventDate = '2016-11-24'
ORDER BY EventTime ASC
LIMIT 5
)
```
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```text
┌─EventID─┬───────────EventTime─┬─delta─┐
│ 1106 │ 2016-11-24 00:00:04 │ 0 │
│ 1107 │ 2016-11-24 00:00:05 │ 1 │
│ 1108 │ 2016-11-24 00:00:05 │ 0 │
│ 1109 │ 2016-11-24 00:00:09 │ 4 │
│ 1110 │ 2016-11-24 00:00:10 │ 1 │
└─────────┴─────────────────────┴───────┘
```
Обратите внимание — размер блока влияет на результат. С каждым новым блоком состояние `runningDifference` сбрасывается.
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```sql
SELECT
number,
runningDifference(number + 1) AS diff
FROM numbers(100000)
WHERE diff != 1
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```
```text
┌─number─┬─diff─┐
│ 0 │ 0 │
└────────┴──────┘
┌─number─┬─diff─┐
│ 65536 │ 0 │
└────────┴──────┘
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```
```
set max_block_size=100000 -- по умолчанию 65536!
SELECT
number,
runningDifference(number + 1) AS diff
FROM numbers(100000)
WHERE diff != 1
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```
```text
┌─number─┬─diff─┐
│ 0 │ 0 │
└────────┴──────┘
```
## runningDifferenceStartingWithFirstValue
То же, что и [runningDifference] (./other_functions.md # other_functions-runningdifference), но в первой строке возвращается значение первой строки, а не ноль.
## MACNumToString(num)
2017-05-10 15:33:41 +00:00
Принимает число типа UInt64. Интерпретирует его, как MAC-адрес в big endian. Возвращает строку, содержащую соответствующий MAC-адрес в формате AA:BB:CC:DD:EE:FF (числа в шестнадцатеричной форме через двоеточие).
## MACStringToNum(s)
2017-05-10 15:33:41 +00:00
Функция, обратная к MACNumToString. Если MAC адрес в неправильном формате, то возвращает 0.
2017-05-15 14:52:47 +00:00
## MACStringToOUI(s)
2017-05-15 14:52:47 +00:00
Принимает MAC адрес в формате AA:BB:CC:DD:EE:FF (числа в шестнадцатеричной форме через двоеточие). Возвращает первые три октета как число в формате UInt64. Если MAC адрес в неправильном формате, то возвращает 0.
## getSizeOfEnumType
WIP on docs (#3813) * CLICKHOUSE-4063: less manual html @ index.md * CLICKHOUSE-4063: recommend markdown="1" in README.md * CLICKHOUSE-4003: manually purge custom.css for now * CLICKHOUSE-4064: expand <details> before any print (including to pdf) * CLICKHOUSE-3927: rearrange interfaces/formats.md a bit * CLICKHOUSE-3306: add few http headers * Remove copy-paste introduced in #3392 * Hopefully better chinese fonts #3392 * get rid of tabs @ custom.css * Apply comments and patch from #3384 * Add jdbc.md to ToC and some translation, though it still looks badly incomplete * minor punctuation * Add some backlinks to official website from mirrors that just blindly take markdown sources * Do not make fonts extra light * find . -name '*.md' -type f | xargs -I{} perl -pi -e 's//g' {} * find . -name '*.md' -type f | xargs -I{} perl -pi -e 's/ sql/g' {} * Remove outdated stuff from roadmap.md * Not so light font on front page too * Refactor Chinese formats.md to match recent changes in other languages * Update some links on front page * Remove some outdated comment * Add twitter link to front page * More front page links tuning * Add Amsterdam meetup link * Smaller font to avoid second line * Add Amsterdam link to README.md * Proper docs nav translation * Back to 300 font-weight except Chinese * fix docs build * Update Amsterdam link * remove symlinks * more zh punctuation * apply lost comment by @zhang2014 * Apply comments by @zhang2014 from #3417 * Remove Beijing link * rm incorrect symlink * restore content of docs/zh/operations/table_engines/index.md * CLICKHOUSE-3751: stem terms while searching docs * CLICKHOUSE-3751: use English stemmer in non-English docs too * CLICKHOUSE-4135 fix * Remove past meetup link * Add blog link to top nav * Add ContentSquare article link * Add form link to front page + refactor some texts * couple markup fixes * minor * Introduce basic ODBC driver page in docs * More verbose 3rd party libs disclaimer * Put third-party stuff into a separate folder * Separate third-party stuff in ToC too * Update links * Move stuff that is not really (only) a client library into a separate page * Add clickhouse-hdfs-loader link * Some introduction for "interfaces" section * Rewrite tcp.md * http_interface.md -> http.md * fix link * Remove unconvenient error for now * try to guess anchor instead of failing * remove symlink * Remove outdated info from introduction * remove ru roadmap.md * replace ru roadmap.md with symlink * Update roadmap.md * lost file * Title case in toc_en.yml * Sync "Functions" ToC section with en * Remove reference to pretty old ClickHouse release from docs * couple lost symlinks in fa * Close quote in proper place * Rewrite en/getting_started/index.md * Sync en<>ru getting_started/index.md * minor changes * Some gui.md refactoring * Translate DataGrip section to ru * Translate DataGrip section to zh * Translate DataGrip section to fa * Translate DBeaver section to fa * Translate DBeaver section to zh * Split third-party GUI to open-source and commercial * Mention some RDBMS integrations + ad-hoc translation fixes * Add rel="external nofollow" to outgoing links from docs * Lost blank lines * Fix class name * More rel="external nofollow" * Apply suggestions by @sundy-li * Mobile version of front page improvements * test * test 2 * test 3 * Update LICENSE * minor docs fix * Highlight current article as suggested by @sundy-li * fix link destination * Introduce backup.md (only "en" for now) * Mention INSERT+SELECT in backup.md * Some improvements for replication.md * Add backup.md to toc * Mention clickhouse-backup tool * Mention LightHouse in third-party GUI list * Introduce interfaces/third-party/proxy.md * Add clickhouse-bulk to proxy.md * Major extension of integrations.md contents * fix link target * remove unneeded file * better toc item name * fix markdown * better ru punctuation * Add yet another possible backup approach * Simplify copying permalinks to headers * Support non-eng link anchors in docs + update some deps * Generate anchors for single-page mode automatically * Remove anchors to top of pages * Remove anchors that nobody links to * build fixes * fix few links * restore css * fix some links * restore gifs * fix lost words * more docs fixes * docs fixes * NULL anchor * update urllib3 dependency * more fixes
2018-12-12 17:28:00 +00:00
Возвращает количество полей в [Enum](../../data_types/enum.md).
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```sql
getSizeOfEnumType(value)
```
**Параметры**
- `value` — Значение типа `Enum`.
**Возвращаемые значения**
- Количество полей входного значения типа `Enum`.
- Исключение, если тип не `Enum`.
**Пример**
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```sql
SELECT getSizeOfEnumType( CAST('a' AS Enum8('a' = 1, 'b' = 2) ) ) AS x
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```text
┌─x─┐
│ 2 │
└───┘
```
## toColumnTypeName
Возвращает имя класса, которым представлен тип данных столбца в оперативной памяти.
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```sql
toColumnTypeName(value)
```
**Параметры**
- `value` — Значение произвольного типа.
**Возвращаемые значения**
- Строка с именем класса, который используется для представления типа данных `value` в оперативной памяти.
**Пример разницы между `toTypeName` и `toColumnTypeName`**
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```sql
SELECT toTypeName(CAST('2018-01-01 01:02:03' AS DateTime))
```
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```text
┌─toTypeName(CAST('2018-01-01 01:02:03', 'DateTime'))─┐
│ DateTime │
└─────────────────────────────────────────────────────┘
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```
```sql
SELECT toColumnTypeName(CAST('2018-01-01 01:02:03' AS DateTime))
```
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```text
┌─toColumnTypeName(CAST('2018-01-01 01:02:03', 'DateTime'))─┐
│ Const(UInt32) │
└───────────────────────────────────────────────────────────┘
```
В примере видно, что тип данных `DateTime` хранится в памяти как `Const(UInt32)`.
## dumpColumnStructure
Выводит развернутое описание структур данных в оперативной памяти
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```sql
dumpColumnStructure(value)
```
**Параметры**
- `value` — Значение произвольного типа.
**Возвращаемые значения**
- Строка с описанием структуры, которая используется для представления типа данных `value` в оперативной памяти.
**Пример**
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```sql
SELECT dumpColumnStructure(CAST('2018-01-01 01:02:03', 'DateTime'))
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```text
┌─dumpColumnStructure(CAST('2018-01-01 01:02:03', 'DateTime'))─┐
│ DateTime, Const(size = 1, UInt32(size = 1)) │
└──────────────────────────────────────────────────────────────┘
```
## defaultValueOfArgumentType
Выводит значение по умолчанию для типа данных.
Не учитывает значения по умолчанию для столбцов, заданные пользователем.
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```sql
defaultValueOfArgumentType(expression)
```
**Параметры**
- `expression` — Значение произвольного типа или выражение, результатом которого является значение произвольного типа.
**Возвращаемые значения**
- `0` для чисел;
- Пустая строка для строк;
WIP on docs (#3813) * CLICKHOUSE-4063: less manual html @ index.md * CLICKHOUSE-4063: recommend markdown="1" in README.md * CLICKHOUSE-4003: manually purge custom.css for now * CLICKHOUSE-4064: expand <details> before any print (including to pdf) * CLICKHOUSE-3927: rearrange interfaces/formats.md a bit * CLICKHOUSE-3306: add few http headers * Remove copy-paste introduced in #3392 * Hopefully better chinese fonts #3392 * get rid of tabs @ custom.css * Apply comments and patch from #3384 * Add jdbc.md to ToC and some translation, though it still looks badly incomplete * minor punctuation * Add some backlinks to official website from mirrors that just blindly take markdown sources * Do not make fonts extra light * find . -name '*.md' -type f | xargs -I{} perl -pi -e 's//g' {} * find . -name '*.md' -type f | xargs -I{} perl -pi -e 's/ sql/g' {} * Remove outdated stuff from roadmap.md * Not so light font on front page too * Refactor Chinese formats.md to match recent changes in other languages * Update some links on front page * Remove some outdated comment * Add twitter link to front page * More front page links tuning * Add Amsterdam meetup link * Smaller font to avoid second line * Add Amsterdam link to README.md * Proper docs nav translation * Back to 300 font-weight except Chinese * fix docs build * Update Amsterdam link * remove symlinks * more zh punctuation * apply lost comment by @zhang2014 * Apply comments by @zhang2014 from #3417 * Remove Beijing link * rm incorrect symlink * restore content of docs/zh/operations/table_engines/index.md * CLICKHOUSE-3751: stem terms while searching docs * CLICKHOUSE-3751: use English stemmer in non-English docs too * CLICKHOUSE-4135 fix * Remove past meetup link * Add blog link to top nav * Add ContentSquare article link * Add form link to front page + refactor some texts * couple markup fixes * minor * Introduce basic ODBC driver page in docs * More verbose 3rd party libs disclaimer * Put third-party stuff into a separate folder * Separate third-party stuff in ToC too * Update links * Move stuff that is not really (only) a client library into a separate page * Add clickhouse-hdfs-loader link * Some introduction for "interfaces" section * Rewrite tcp.md * http_interface.md -> http.md * fix link * Remove unconvenient error for now * try to guess anchor instead of failing * remove symlink * Remove outdated info from introduction * remove ru roadmap.md * replace ru roadmap.md with symlink * Update roadmap.md * lost file * Title case in toc_en.yml * Sync "Functions" ToC section with en * Remove reference to pretty old ClickHouse release from docs * couple lost symlinks in fa * Close quote in proper place * Rewrite en/getting_started/index.md * Sync en<>ru getting_started/index.md * minor changes * Some gui.md refactoring * Translate DataGrip section to ru * Translate DataGrip section to zh * Translate DataGrip section to fa * Translate DBeaver section to fa * Translate DBeaver section to zh * Split third-party GUI to open-source and commercial * Mention some RDBMS integrations + ad-hoc translation fixes * Add rel="external nofollow" to outgoing links from docs * Lost blank lines * Fix class name * More rel="external nofollow" * Apply suggestions by @sundy-li * Mobile version of front page improvements * test * test 2 * test 3 * Update LICENSE * minor docs fix * Highlight current article as suggested by @sundy-li * fix link destination * Introduce backup.md (only "en" for now) * Mention INSERT+SELECT in backup.md * Some improvements for replication.md * Add backup.md to toc * Mention clickhouse-backup tool * Mention LightHouse in third-party GUI list * Introduce interfaces/third-party/proxy.md * Add clickhouse-bulk to proxy.md * Major extension of integrations.md contents * fix link target * remove unneeded file * better toc item name * fix markdown * better ru punctuation * Add yet another possible backup approach * Simplify copying permalinks to headers * Support non-eng link anchors in docs + update some deps * Generate anchors for single-page mode automatically * Remove anchors to top of pages * Remove anchors that nobody links to * build fixes * fix few links * restore css * fix some links * restore gifs * fix lost words * more docs fixes * docs fixes * NULL anchor * update urllib3 dependency * more fixes
2018-12-12 17:28:00 +00:00
- `ᴺᵁᴸᴸ` для [Nullable](../../data_types/nullable.md).
**Пример**
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```sql
SELECT defaultValueOfArgumentType( CAST(1 AS Int8) )
```
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```text
┌─defaultValueOfArgumentType(CAST(1, 'Int8'))─┐
│ 0 │
└─────────────────────────────────────────────┘
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```
```sql
SELECT defaultValueOfArgumentType( CAST(1 AS Nullable(Int8) ) )
```
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```text
┌─defaultValueOfArgumentType(CAST(1, 'Nullable(Int8)'))─┐
│ ᴺᵁᴸᴸ │
└───────────────────────────────────────────────────────┘
```
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## replicate {#other_functions-replicate}
Создает массив, заполненный одним значением.
Используется для внутренней реализации [arrayJoin](array_join.md#functions_arrayjoin).
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```sql
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SELECT replicate(x, arr);
```
**Параметры**
- `arr` — Исходный массив. ClickHouse создаёт новый массив такой же длины как исходный и заполняет его значением `x`.
- `x` — Значение, которым будет заполнен результирующий массив.
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**Возвращаемое значение**
Массив, заполненный значением `x`.
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Тип: `Array`.
**Пример**
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Запрос:
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```sql
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SELECT replicate(1, ['a', 'b', 'c']);
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```
2019-09-30 09:17:55 +00:00
Ответ:
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```text
┌─replicate(1, ['a', 'b', 'c'])─┐
│ [1,1,1] │
└───────────────────────────────┘
```
## filesystemAvailable {#filesystemavailable}
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Возвращает объём доступного для записи данных места на файловой системе. Он всегда меньше общего свободного места ([filesystemFree](#filesystemfree)), потому что некоторое пространство зарезервировано для нужд операционной системы.
**Синтаксис**
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```sql
filesystemAvailable()
```
**Возвращаемое значение**
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- Объём доступного для записи данных места в байтах.
Тип: [UInt64](../../data_types/int_uint.md).
**Пример**
Запрос:
```sql
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SELECT formatReadableSize(filesystemAvailable()) AS "Available space", toTypeName(filesystemAvailable()) AS "Type";
```
Ответ:
```text
┌─Available space─┬─Type───┐
2019-11-11 11:41:33 +00:00
│ 30.75 GiB │ UInt64 │
└─────────────────┴────────┘
```
## filesystemFree {#filesystemfree}
2020-02-02 21:43:39 +00:00
Возвращает объём свободного места на файловой системе. Смотрите также `filesystemAvailable`.
**Синтаксис**
```sql
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filesystemFree()
```
**Возвращаемое значение**
- Объем свободного места в байтах.
Тип: [UInt64](../../data_types/int_uint.md).
**Пример**
Запрос:
```sql
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SELECT formatReadableSize(filesystemFree()) AS "Free space", toTypeName(filesystemFree()) AS "Type";
```
Ответ:
```text
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┌─Free space─┬─Type───┐
│ 32.39 GiB │ UInt64 │
└────────────┴────────┘
```
## filesystemCapacity {#filesystemcapacity}
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Возвращает информацию о ёмкости файловой системы в байтах. Для оценки должен быть настроен [путь](../../operations/server_settings/settings.md#server_settings-path) к каталогу с данными.
**Синтаксис**
```sql
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filesystemCapacity()
```
**Возвращаемое значение**
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- Информация о ёмкости файловой системы в байтах.
Тип: [UInt64](../../data_types/int_uint.md).
**Пример**
Запрос:
```sql
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SELECT formatReadableSize(filesystemCapacity()) AS "Capacity", toTypeName(filesystemCapacity()) AS "Type"
```
Ответ:
```text
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┌─Capacity──┬─Type───┐
│ 39.32 GiB │ UInt64 │
└───────────┴────────┘
```
## finalizeAggregation {#function-finalizeaggregation}
Принимает состояние агрегатной функции. Возвращает результат агрегирования.
## runningAccumulate {#function-runningaccumulate}
Принимает на вход состояния агрегатной функции и возвращает столбец со значениями, которые представляют собой результат мёржа этих состояний для выборки строк из блока от первой до текущей строки. Например, принимает состояние агрегатной функции (например, `runningAccumulate(uniqState(UserID))`), и для каждой строки блока возвращает результат агрегатной функции после мёржа состояний функции для всех предыдущих строк и текущей. Таким образом, результат зависит от разбиения данных по блокам и от порядка данных в блоке.
## joinGet {#joinget}
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Функция позволяет извлекать данные из таблицы таким же образом как из [словаря](../../query_language/dicts/index.md).
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Получает данные из таблиц [Join](../../operations/table_engines/join.md#creating-a-table) по ключу.
Поддерживаются только таблицы, созданные с `ENGINE = Join(ANY, LEFT, <join_keys>)`.
**Синтаксис**
```sql
joinGet(join_storage_table_name, `value_column`, join_keys)
```
**Параметры**
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- `join_storage_table_name` — [идентификатор](../syntax.md#syntax-identifiers), который указывает, откуда производится выборка данных. Поиск по идентификатору осуществляется в базе данных по умолчанию (см. конфигурацию `default_database`). Чтобы переопределить базу данных по умолчанию, используйте команду `USE db_name`, или укажите базу данных и таблицу через разделитель `db_name.db_table`, см. пример.
- `value_column` — столбец, из которого нужно произвести выборку данных.
- `join_keys` — список ключей, по которым производится выборка данных.
**Возвращаемое значение**
Возвращает значение по списку ключей.
Если значения не существует в исходной таблице, вернется `0` или `null` в соответствии с настройками [join_use_nulls](../../operations/settings/settings.md#join_use_nulls).
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Подробнее о настройке `join_use_nulls` в [операциях Join](../../operations/table_engines/join.md).
**Пример**
Входная таблица:
```sql
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CREATE DATABASE db_test
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CREATE TABLE db_test.id_val(`id` UInt32, `val` UInt32) ENGINE = Join(ANY, LEFT, id) SETTINGS join_use_nulls = 1
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INSERT INTO db_test.id_val VALUES (1,11)(2,12)(4,13)
```
```text
┌─id─┬─val─┐
│ 4 │ 13 │
│ 2 │ 12 │
│ 1 │ 11 │
└────┴─────┘
```
Запрос:
```sql
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SELECT joinGet(db_test.id_val,'val',toUInt32(number)) from numbers(4) SETTINGS join_use_nulls = 1
```
Результат:
```text
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┌─joinGet(db_test.id_val, 'val', toUInt32(number))─┐
│ 0 │
│ 11 │
│ 12 │
│ 0 │
└──────────────────────────────────────────────────┘
```
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## modelEvaluate(model_name, ...) {#function-modelevaluate}
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Оценивает внешнюю модель.
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Принимает на вход имя и аргументы модели. Возвращает Float64.
## throwIf(x\[, custom_message\])
Бросает исключение, если аргумент не равен нулю.
custom_message - необязательный параметр, константная строка, задает текст сообщения об ошибке.
```sql
SELECT throwIf(number = 3, 'Too many') FROM numbers(10);
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
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```
```text
↙ Progress: 0.00 rows, 0.00 B (0.00 rows/s., 0.00 B/s.) Received exception from server (version 19.14.1):
Code: 395. DB::Exception: Received from localhost:9000. DB::Exception: Too many.
```
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## identity {#identity}
Возвращает свой аргумент. Используется для отладки и тестирования, позволяет отменить использование индекса, и получить результат и производительность полного сканирования таблицы. Это работает, потому что оптимизатор запросов не может "заглянуть" внутрь функции `identity`.
**Синтаксис**
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```sql
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identity(x)
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```
**Пример**
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Query:
```sql
SELECT identity(42)
DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
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```
Результат:
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DOCAPI-8530: Code blocks markup fix (#7060) * Typo fix. * Links fix. * Fixed links in docs. * More fixes. * docs/en: cleaning some files * docs/en: cleaning data_types * docs/en: cleaning database_engines * docs/en: cleaning development * docs/en: cleaning getting_started * docs/en: cleaning interfaces * docs/en: cleaning operations * docs/en: cleaning query_lamguage * docs/en: cleaning en * docs/ru: cleaning data_types * docs/ru: cleaning index * docs/ru: cleaning database_engines * docs/ru: cleaning development * docs/ru: cleaning general * docs/ru: cleaning getting_started * docs/ru: cleaning interfaces * docs/ru: cleaning operations * docs/ru: cleaning query_language * docs: cleaning interfaces/http * Update docs/en/data_types/array.md decorated ``` Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/nyc_taxi.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/getting_started/example_datasets/ontime.md fixed typo Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/interfaces/formats.md fixed error Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/custom_partitioning_key.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/dicts/external_dicts_dict_sources.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/utils/clickhouse-local.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/json_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/other_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/query_language/functions/date_time_functions.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * Update docs/en/operations/table_engines/jdbc.md Co-Authored-By: BayoNet <da-daos@yandex.ru> * docs: fixed error * docs: fixed error
2019-09-23 15:31:46 +00:00
```text
┌─identity(42)─┐
│ 42 │
└──────────────┘
```
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## randomPrintableASCII {#randomascii}
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Генерирует строку со случайным набором печатных символов [ASCII](https://en.wikipedia.org/wiki/ASCII#Printable_characters).
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**Синтаксис**
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```sql
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randomPrintableASCII(length)
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```
**Параметры**
- `length` — Длина результирующей строки. Положительное целое число.
Если передать `length < 0`, то поведение функции не определено.
**Возвращаемое значение**
- Строка со случайным набором печатных символов [ASCII](https://en.wikipedia.org/wiki/ASCII#Printable_characters).
Тип: [String](../../data_types/string.md)
**Пример**
```sql
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SELECT number, randomPrintableASCII(30) as str, length(str) FROM system.numbers LIMIT 3
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```
```text
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┌─number─┬─str────────────────────────────┬─length(randomPrintableASCII(30))─┐
│ 0 │ SuiCOSTvC0csfABSw=UcSzp2.`rv8x │ 30 │
│ 1 │ 1Ag NlJ &RCN:*>HVPG;PE-nO"SUFD │ 30 │
│ 2 │ /"+<"wUTh:=LjJ Vm!c&hI*m#XTfzz │ 30 │
└────────┴────────────────────────────────┴──────────────────────────────────┘
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```
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[Оригинальная статья](https://clickhouse.tech/docs/ru/query_language/functions/other_functions/) <!--hide-->