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set args

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This commit is contained in:
Nikita Vasilev 2019-02-13 22:29:31 +03:00
parent ca1484ae95
commit 04a62f3df4
2 changed files with 4 additions and 6 deletions
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6
docs/en/operations/table_engines/mergetree.md
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@ -252,7 +252,7 @@ CREATE TABLE table_name
s String,
...
INDEX a (u64 * i32, s) TYPE minmax GRANULARITY 3,
INDEX b (u64 * length(s)) TYPE set GRANULARITY 4
INDEX b (u64 * length(s)) TYPE set(1000) GRANULARITY 4
) ENGINE = MergeTree()
...
```
@ -269,12 +269,10 @@ SELECT count() FROM table WHERE u64 * i32 == 10 AND u64 * length(s) >= 1234
Stores extremes of the specified expression (if the expression is `tuple`, then it stores extremes for each element of `tuple`), uses stored info for skipping blocks of the data like the primary key.
* `set(max_rows)`
Stores unique values of the specified expression (no more than `max_rows` rows), use them to check if the `WHERE` expression is not satisfiable on a block of the data.
If `max_rows=0`, then there are no limits for storing values. `set` without parameters is equal to `set(0)`.
Stores unique values of the specified expression (no more than `max_rows` rows), use them to check if the `WHERE` expression is not satisfiable on a block of the data.
```sql
INDEX sample_index (u64 * length(s)) TYPE minmax GRANULARITY 4
INDEX b (u64 * length(str), i32 + f64 * 100, date, str) TYPE set GRANULARITY 4
INDEX b (u64 * length(str), i32 + f64 * 100, date, str) TYPE set(100) GRANULARITY 4
```

4
docs/ru/operations/table_engines/mergetree.md
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@ -243,7 +243,7 @@ CREATE TABLE table_name
s String,
...
INDEX a (u64 * i32, s) TYPE minmax GRANULARITY 3,
INDEX b (u64 * length(s), i32) TYPE set GRANULARITY 4
INDEX b (u64 * length(s), i32) TYPE set(1000) GRANULARITY 4
) ENGINE = MergeTree()
...
```
@ -261,7 +261,7 @@ SELECT count() FROM table WHERE u64 * i32 == 10 AND u64 * length(s) >= 1234
* `set(max_rows)`
Хранит уникальные значения выражения на блоке в количестве не более `max_rows`, используя их для пропуска блоков, оценивая выполнимость `WHERE` выражения на хранимых данных.
Если `max_rows=0`, то хранит значения выражения без ограничений. Если параметров не передано, то полагается `max_rows=0`.
Примеры