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[WIP] Add documentation for dictionaries DDL (#7720)
This commit is contained in:
alesapin
Ivan Blinkov
parent
30acb1b653
commit
b26ac93731
@ -271,3 +271,27 @@ Views look the same as normal tables. For example, they are listed in the result
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There isn't a separate query for deleting views. To delete a view, use `DROP TABLE`.
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[Original article](https://clickhouse.yandex/docs/en/query_language/create/) <!--hide-->
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## CREATE DICTIONARY {#create-dictionary-query}
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```sql
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CREATE DICTIONARY [IF NOT EXISTS] [db.]dictionary_name
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(
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key1 type1 [DEFAULT|EXPRESSION expr1] [HIERARCHICAL|INJECTIVE|IS_OBJECT_ID],
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key2 type2 [DEFAULT|EXPRESSION expr2] [HIERARCHICAL|INJECTIVE|IS_OBJECT_ID],
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attr1 type2 [DEFAULT|EXPRESSION expr3],
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attr2 type2 [DEFAULT|EXPRESSION expr4]
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)
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PRIMARY KEY key1, key2
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SOURCE(SOURCE_NAME([param1 value1 ... paramN valueN]))
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LAYOUT(LAYOUT_NAME([param_name param_value]))
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LIFETIME([MIN val1] MAX val2)
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```
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Creates [external dictionary](dicts/external_dicts.md) with given [structure](dicts/external_dicts_dict_structure.md), [source](dicts/external_dicts_dict_sources.md), [layout](dicts/external_dicts_dict_layout.md) and [lifetime](dicts/external_dicts_dict_lifetime.md).
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External dictionary structure consists of attributes. Dictionary attributes are specified similarly to table columns. The only required attribute property is its type, all other properties may have default values.
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Depending on dictionary [layout](dicts/external_dicts_dict_layout.md) one or more attributes can be specified as dictionary keys.
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For more information, see [External Dictionaries](dicts/external_dicts.md) section.
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@ -4,10 +4,11 @@ You can add your own dictionaries from various data sources. The data source for
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ClickHouse:
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> - Fully or partially stores dictionaries in RAM.
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- Fully or partially stores dictionaries in RAM.
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- Periodically updates dictionaries and dynamically loads missing values. In other words, dictionaries can be loaded dynamically.
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- Allows to create external dictionaries with xml-files or [DDL queries](../create.md#create-dictionary-query).
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The configuration of external dictionaries is located in one or more files. The path to the configuration is specified in the [dictionaries_config](../../operations/server_settings/settings.md#server_settings-dictionaries_config) parameter.
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The configuration of external dictionaries can be located in one or more xml-files. The path to the configuration is specified in the [dictionaries_config](../../operations/server_settings/settings.md#server_settings-dictionaries_config) parameter.
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Dictionaries can be loaded at server startup or at first use, depending on the [dictionaries_lazy_load](../../operations/server_settings/settings.md#server_settings-dictionaries_lazy_load) setting.
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@ -31,6 +32,8 @@ The dictionary configuration file has the following format:
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You can [configure](external_dicts_dict.md) any number of dictionaries in the same file.
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[DDL queries for dictionaries](../create.md#create-dictionary-query) doesn't require any additional records in server configuration. They allow to work with dictionaries as first-class entities, like tables or views.
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!!! attention
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You can convert values for a small dictionary by describing it in a `SELECT` query (see the [transform](../functions/other_functions.md) function). This functionality is not related to external dictionaries.
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@ -1,11 +1,15 @@
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# Configuring an External Dictionary {#dicts-external_dicts_dict}
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The dictionary configuration has the following structure:
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If dictionary is configured using xml-file, than dictionary configuration has the following structure:
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```xml
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<dictionary>
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<name>dict_name</name>
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<structure>
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<!-- Complex key configuration -->
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</structure>
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<source>
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<!-- Source configuration -->
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</source>
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@ -14,16 +18,25 @@ The dictionary configuration has the following structure:
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<!-- Memory layout configuration -->
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</layout>
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<structure>
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<!-- Complex key configuration -->
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</structure>
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<lifetime>
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<!-- Lifetime of dictionary in memory -->
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</lifetime>
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</dictionary>
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```
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Corresponding [DDL-query](../create.md#create-dictionary-query) has the following structure:
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```sql
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CREATE DICTIONARY dict_name
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(
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... -- attributes
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)
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PRIMARY KEY ... -- complex or single key configuration
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SOURCE(...) -- Source configuration
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LAYOUT(...) -- Memory layout configuration
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LIFETIME(...) -- Lifetime of dictionary in memory
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```
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- name – The identifier that can be used to access the dictionary. Use the characters `[a-zA-Z0-9_\-]`.
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- [source](external_dicts_dict_sources.md) — Source of the dictionary.
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- [layout](external_dicts_dict_layout.md) — Dictionary layout in memory.
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@ -34,6 +34,15 @@ The configuration looks like this:
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</yandex>
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```
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in case of [DDL-query](../create.md#create-dictionary-query), equal configuration will looks like
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```sql
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CREATE DICTIONARY (...)
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...
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LAYOUT(LAYOUT_TYPE(param value)) -- layout settings
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...
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```
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## Ways to Store Dictionaries in Memory
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@ -64,6 +73,12 @@ Configuration example:
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</layout>
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```
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or
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```sql
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LAYOUT(FLAT())
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```
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### hashed {#dicts-external_dicts_dict_layout-hashed}
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The dictionary is completely stored in memory in the form of a hash table. The dictionary can contain any number of elements with any identifiers In practice, the number of keys can reach tens of millions of items.
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@ -78,6 +93,12 @@ Configuration example:
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</layout>
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```
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or
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```sql
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LAYOUT(HASHED())
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```
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### sparse_hashed {#dicts-external_dicts_dict_layout-sparse_hashed}
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Similar to `hashed`, but uses less memory in favor more CPU usage.
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@ -90,6 +111,9 @@ Configuration example:
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</layout>
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```
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```sql
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LAYOUT(SPARSE_HASHED())
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```
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### complex_key_hashed
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@ -103,6 +127,9 @@ Configuration example:
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</layout>
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```
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```sql
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LAYOUT(COMPLEX_KEY_HASHED())
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```
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### range_hashed
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@ -113,15 +140,15 @@ This storage method works the same way as hashed and allows using date/time (arb
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Example: The table contains discounts for each advertiser in the format:
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```text
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+---------------+---------------------+-------------------+--------+
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+---------------|---------------------|-------------------|--------+
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| advertiser id | discount start date | discount end date | amount |
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+===============+=====================+===================+========+
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| 123 | 2015-01-01 | 2015-01-15 | 0.15 |
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+---------------+---------------------+-------------------+--------+
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+---------------|---------------------|-------------------|--------+
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| 123 | 2015-01-16 | 2015-01-31 | 0.25 |
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+---------------+---------------------+-------------------+--------+
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+---------------|---------------------|-------------------|--------+
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| 456 | 2015-01-01 | 2015-01-15 | 0.05 |
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+---------------+---------------------+-------------------+--------+
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+---------------|---------------------|-------------------|--------+
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```
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To use a sample for date ranges, define the `range_min` and `range_max` elements in the [structure](external_dicts_dict_structure.md). These elements must contain elements `name` and` type` (if `type` is not specified, the default type will be used - Date). `type` can be any numeric type (Date / DateTime / UInt64 / Int32 / others).
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@ -144,6 +171,19 @@ Example:
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...
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```
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or
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```sql
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CREATE DICTIONARY somedict (
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id UInt64,
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first Date,
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last Date
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)
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PRIMARY KEY id
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LAYOUT(RANGE_HASHED())
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RANGE(MIN first MAX last)
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```
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To work with these dictionaries, you need to pass an additional argument to the `dictGetT` function, for which a range is selected:
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```sql
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@ -193,6 +233,18 @@ Configuration example:
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</yandex>
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```
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or
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```sql
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CREATE DICTIONARY somedict(
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Abcdef UInt64,
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StartTimeStamp UInt64,
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EndTimeStamp UInt64,
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XXXType String DEFAULT ''
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)
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PRIMARY KEY Abcdef
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RANGE(MIN StartTimeStamp MAX EndTimeStamp)
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```
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### cache
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@ -218,6 +270,12 @@ Example of settings:
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</layout>
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```
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or
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```sql
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LAYOUT(CACHE(SIZE_IN_CELLS 1000000000))
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```
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Set a large enough cache size. You need to experiment to select the number of cells:
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1. Set some value.
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@ -241,17 +299,17 @@ This type of storage is for mapping network prefixes (IP addresses) to metadata
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Example: The table contains network prefixes and their corresponding AS number and country code:
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```text
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+-----------------+-------+--------+
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+-----------------|-------|--------+
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| prefix | asn | cca2 |
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+=================+=======+========+
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| 202.79.32.0/20 | 17501 | NP |
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+-----------------+-------+--------+
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+-----------------|-------|--------+
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| 2620:0:870::/48 | 3856 | US |
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+-----------------+-------+--------+
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+-----------------|-------|--------+
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| 2a02:6b8:1::/48 | 13238 | RU |
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+-----------------+-------+--------+
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+-----------------|-------|--------+
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| 2001:db8::/32 | 65536 | ZZ |
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+-----------------+-------+--------+
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+-----------------|-------|--------+
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```
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When using this type of layout, the structure must have a composite key.
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@ -279,6 +337,17 @@ Example:
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...
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```
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or
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```sql
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CREATE DICTIONARY somedict (
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prefix String,
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asn UInt32,
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cca2 String DEFAULT '??'
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)
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PRIMARY KEY prefix
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```
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The key must have only one String type attribute that contains an allowed IP prefix. Other types are not supported yet.
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For queries, you must use the same functions (`dictGetT` with a tuple) as for dictionaries with composite keys:
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@ -15,7 +15,14 @@ Example of settings:
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</dictionary>
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```
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Setting ` <lifetime> 0</lifetime> ` prevents updating dictionaries.
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```sql
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CREATE DICTIONARY (...)
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...
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LIFETIME(300)
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...
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```
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Setting `<lifetime>0</lifetime>` (`LIFETIME(0)`) prevents dictionaries from updating.
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You can set a time interval for upgrades, and ClickHouse will choose a uniformly random time within this range. This is necessary in order to distribute the load on the dictionary source when upgrading on a large number of servers.
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@ -32,6 +39,12 @@ Example of settings:
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</dictionary>
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```
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or
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```sql
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LIFETIME(MIN 300 MAX 360)
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```
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When upgrading the dictionaries, the ClickHouse server applies different logic depending on the type of [ source](external_dicts_dict_sources.md):
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- For a text file, it checks the time of modification. If the time differs from the previously recorded time, the dictionary is updated.
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@ -56,5 +69,13 @@ Example of settings:
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</dictionary>
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```
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or
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```sql
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...
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SOURCE(ODBC(... invalidate_query 'SELECT update_time FROM dictionary_source where id = 1'))
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...
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```
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[Original article](https://clickhouse.yandex/docs/en/query_language/dicts/external_dicts_dict_lifetime/) <!--hide-->
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@ -2,7 +2,7 @@
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An external dictionary can be connected from many different sources.
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The configuration looks like this:
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If dictionary is configured using xml-file, the configuration looks like this:
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```xml
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<yandex>
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@ -19,6 +19,15 @@ The configuration looks like this:
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</yandex>
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```
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In case of [DDL-query](../create.md#create-dictionary-query), equal configuration will looks like:
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```sql
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CREATE DICTIONARY dict_name (...)
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...
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SOURCE(SOURCE_TYPE(param1 val1 ... paramN valN)) -- Source configuration
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...
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```
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The source is configured in the `source` section.
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Types of sources (`source_type`):
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@ -47,6 +56,12 @@ Example of settings:
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</source>
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```
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or
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```sql
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SOURCE(FILE(path '/opt/dictionaries/os.tsv' format 'TabSeparated'))
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```
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Setting fields:
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- `path` – The absolute path to the file.
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@ -68,6 +83,12 @@ Example of settings:
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</source>
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```
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or
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```sql
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SOURCE(EXECUTABLE(command 'cat /opt/dictionaries/os.tsv' format 'TabSeparated'))
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```
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Setting fields:
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- `command` – The absolute path to the executable file, or the file name (if the program directory is written to `PATH`).
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@ -99,6 +120,17 @@ Example of settings:
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</source>
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```
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or
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```sql
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SOURCE(HTTP(
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url 'http://[::1]/os.tsv'
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format 'TabSeparated'
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credentials(user 'user' password 'password')
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headers(header(name 'API-KEY' value 'key'))
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))
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```
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In order for ClickHouse to access an HTTPS resource, you must [configure openSSL](../../operations/server_settings/settings.md#server_settings-openssl) in the server configuration.
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Setting fields:
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@ -121,12 +153,25 @@ You can use this method to connect any database that has an ODBC driver.
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Example of settings:
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```xml
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<odbc>
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<db>DatabaseName</db>
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<table>ShemaName.TableName</table>
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<connection_string>DSN=some_parameters</connection_string>
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<invalidate_query>SQL_QUERY</invalidate_query>
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</odbc>
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<source>
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<odbc>
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<db>DatabaseName</db>
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<table>ShemaName.TableName</table>
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<connection_string>DSN=some_parameters</connection_string>
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<invalidate_query>SQL_QUERY</invalidate_query>
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</odbc>
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</source>
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```
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or
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```sql
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SOURCE(ODBC(
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db 'DatabaseName'
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table 'SchemaName.TableName'
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connection_string 'DSN=some_parameters'
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invalidate_query 'SQL_QUERY'
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))
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```
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Setting fields:
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@ -233,6 +278,19 @@ The dictionary configuration in ClickHouse:
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</yandex>
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```
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or
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```sql
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CREATE DICTIONARY table_name (
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id UInt64,
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some_column UInt64 DEFAULT 0
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)
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PRIMARY KEY id
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SOURCE(ODBC(connection_string 'DSN=myconnection' table 'postgresql_table'))
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LAYOUT(HASHED())
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LIFETIME(MIN 300 MAX 360)
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```
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You may need to edit `odbc.ini` to specify the full path to the library with the driver `DRIVER=/usr/local/lib/psqlodbcw.so`.
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### Example of Connecting MS SQL Server
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@ -316,6 +374,19 @@ Configuring the dictionary in ClickHouse:
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</yandex>
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```
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or
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```sql
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CREATE DICTIONARY test (
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k UInt64,
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s String DEFAULT ''
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)
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PRIMARY KEY k
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SOURCE(ODBC(table 'dict' connection_string 'DSN=MSSQL;UID=test;PWD=test'))
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LAYOUT(FLAT())
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LIFETIME(MIN 300 MAX 360)
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```
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## DBMS
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@ -345,6 +416,22 @@ Example of settings:
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</source>
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```
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or
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```sql
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SOURCE(MYSQL(
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port 3306
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user 'clickhouse'
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password 'qwerty'
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replica(host 'example01-1' priority 1)
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replica(host 'example01-2' priority 1)
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db 'db_name'
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table 'table_name'
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where 'id=10'
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invalidate_query 'SQL_QUERY'
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))
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```
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Setting fields:
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- `port` – The port on the MySQL server. You can specify it for all replicas, or for each one individually (inside `<replica>`).
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@ -385,6 +472,21 @@ Example of settings:
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</source>
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||||
```
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||||
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||||
or
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||||
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||||
```sql
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SOURCE(MYSQL(
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host 'localhost'
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socket '/path/to/socket/file.sock'
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user 'clickhouse'
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password 'qwerty'
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db 'db_name'
|
||||
table 'table_name'
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where 'id=10'
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invalidate_query 'SQL_QUERY'
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))
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```
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|
||||
|
||||
### ClickHouse {#dicts-external_dicts_dict_sources-clickhouse}
|
||||
|
||||
@ -404,6 +506,20 @@ Example of settings:
|
||||
</source>
|
||||
```
|
||||
|
||||
or
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||||
|
||||
```sql
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||||
SOURCE(CLICKHOUSE(
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host 'example01-01-1'
|
||||
port 9000
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||||
user 'default'
|
||||
password ''
|
||||
db 'default'
|
||||
table 'ids'
|
||||
where 'id=10'
|
||||
))
|
||||
```
|
||||
|
||||
Setting fields:
|
||||
|
||||
- `host` – The ClickHouse host. If it is a local host, the query is processed without any network activity. To improve fault tolerance, you can create a [Distributed](../../operations/table_engines/distributed.md) table and enter it in subsequent configurations.
|
||||
@ -433,6 +549,19 @@ Example of settings:
|
||||
</source>
|
||||
```
|
||||
|
||||
or
|
||||
|
||||
```sql
|
||||
SOURCE(MONGO(
|
||||
host 'localhost'
|
||||
port 27017
|
||||
user ''
|
||||
password ''
|
||||
db 'test'
|
||||
collection 'dictionary_source'
|
||||
))
|
||||
```
|
||||
|
||||
Setting fields:
|
||||
|
||||
- `host` – The MongoDB host.
|
||||
@ -458,6 +587,17 @@ Example of settings:
|
||||
</source>
|
||||
```
|
||||
|
||||
or
|
||||
|
||||
```sql
|
||||
SOURCE(REDIS(
|
||||
host 'localhost'
|
||||
port 6379
|
||||
storage_type 'simple'
|
||||
db_index 0
|
||||
))
|
||||
```
|
||||
|
||||
Setting fields:
|
||||
|
||||
- `host` – The Redis host.
|
||||
|
||||
@ -22,23 +22,35 @@ Overall structure:
|
||||
</dictionary>
|
||||
```
|
||||
|
||||
Columns are described in the structure:
|
||||
or
|
||||
|
||||
```sql
|
||||
CREATE DICTIONARY (
|
||||
Id UInt64,
|
||||
-- attributes
|
||||
)
|
||||
PRIMARY KEY Id
|
||||
...
|
||||
```
|
||||
|
||||
|
||||
In xml-file attributes are described in the structure section:
|
||||
|
||||
- `<id>` — [Key column](external_dicts_dict_structure.md#ext_dict_structure-key).
|
||||
- `<attribute>` — [Data column](external_dicts_dict_structure.md#ext_dict_structure-attributes). There can be a large number of columns.
|
||||
- `<attribute>` — [Data column](external_dicts_dict_structure.md#ext_dict_structure-attributes). There can be a large number of attributes.
|
||||
|
||||
In DDL-query attributes are described the body of `CREATE` query:
|
||||
- `PRIMARY KEY` — [Key column](external_dicts_dict_structure.md#ext_dict_structure-key)
|
||||
- `AttrName AttrType` — [Data column](external_dicts_dict_structure.md#ext_dict_structure-attributes)
|
||||
|
||||
## Key {#ext_dict_structure-key}
|
||||
|
||||
ClickHouse supports the following types of keys:
|
||||
|
||||
- Numeric key. UInt64. Defined in the tag `<id>` .
|
||||
- Composite key. Set of values of different types. Defined in the tag `<key>` .
|
||||
- Numeric key. UInt64. Defined in the `<id>` tag or using `PRIMARY KEY` keyword.
|
||||
- Composite key. Set of values of different types. Defined in the tag `<key>` or `PRIMARY KEY` keyword.
|
||||
|
||||
A structure can contain either `<id>` or `<key>` .
|
||||
|
||||
!!! warning
|
||||
The key doesn't need to be defined separately in attributes.
|
||||
A xml-structure can contain either `<id>` or `<key>`. DDL-query must contain single `PRIMARY KEY`.
|
||||
|
||||
### Numeric Key
|
||||
|
||||
@ -56,6 +68,20 @@ Configuration fields:
|
||||
|
||||
- `name` – The name of the column with keys.
|
||||
|
||||
|
||||
For DDL-query:
|
||||
|
||||
```sql
|
||||
CREATE DICTIONARY (
|
||||
Id UInt64,
|
||||
...
|
||||
)
|
||||
PRIMARY KEY Id
|
||||
...
|
||||
```
|
||||
|
||||
- `PRIMARY KEY` – The name of the column with keys.
|
||||
|
||||
### Composite Key
|
||||
|
||||
The key can be a `tuple` from any types of fields. The [layout](external_dicts_dict_layout.md) in this case must be `complex_key_hashed` or `complex_key_cache`.
|
||||
@ -81,6 +107,18 @@ The key structure is set in the element `<key>`. Key fields are specified in the
|
||||
...
|
||||
```
|
||||
|
||||
or
|
||||
|
||||
```sql
|
||||
CREATE DICTIONARY (
|
||||
field1 String,
|
||||
field2 String
|
||||
...
|
||||
)
|
||||
PRIMARY KEY field1, field2
|
||||
...
|
||||
```
|
||||
|
||||
For a query to the `dictGet*` function, a tuple is passed as the key. Example: `dictGetString('dict_name', 'attr_name', tuple('string for field1', num_for_field2))`.
|
||||
|
||||
|
||||
@ -103,6 +141,14 @@ Configuration example:
|
||||
</structure>
|
||||
```
|
||||
|
||||
or
|
||||
|
||||
```sql
|
||||
CREATE DICTIONARY somename (
|
||||
Name ClickHouseDataType DEFAULT '' EXPRESSION rand64() HIERARCHICAL INJECTIVE IS_OBJECT_ID
|
||||
)
|
||||
```
|
||||
|
||||
Configuration fields:
|
||||
|
||||
Tag | Description | Required
|
||||
|
||||
@ -101,10 +101,17 @@ DROP [TEMPORARY] TABLE [IF EXISTS] [db.]name [ON CLUSTER cluster]
|
||||
Deletes the table.
|
||||
If `IF EXISTS` is specified, it doesn't return an error if the table doesn't exist or the database doesn't exist.
|
||||
|
||||
```
|
||||
DROP DICTIONARY [IF EXISTS] [db.]name
|
||||
```
|
||||
|
||||
Delets the dictionary.
|
||||
If `IF EXISTS` is specified, it doesn't return an error if the table doesn't exist or the database doesn't exist.
|
||||
|
||||
## EXISTS
|
||||
|
||||
```sql
|
||||
EXISTS [TEMPORARY] TABLE [db.]name [INTO OUTFILE filename] [FORMAT format]
|
||||
EXISTS [TEMPORARY] [TABLE|DICTIONARY] [db.]name [INTO OUTFILE filename] [FORMAT format]
|
||||
```
|
||||
|
||||
Returns a single `UInt8`-type column, which contains the single value `0` if the table or database doesn't exist, or `1` if the table exists in the specified database.
|
||||
|
||||
@ -3,10 +3,10 @@
|
||||
## SHOW CREATE TABLE
|
||||
|
||||
```sql
|
||||
SHOW CREATE [TEMPORARY] TABLE [db.]table [INTO OUTFILE filename] [FORMAT format]
|
||||
SHOW CREATE [TEMPORARY] [TABLE|DICTIONARY] [db.]table [INTO OUTFILE filename] [FORMAT format]
|
||||
```
|
||||
|
||||
Returns a single `String`-type 'statement' column, which contains a single value – the `CREATE` query used for creating the specified table.
|
||||
Returns a single `String`-type 'statement' column, which contains a single value – the `CREATE` query used for creating the specified object.
|
||||
|
||||
## SHOW DATABASES {#show-databases}
|
||||
|
||||
@ -62,3 +62,33 @@ SHOW TABLES FROM system LIKE '%co%' LIMIT 2
|
||||
│ collations │
|
||||
└────────────────────────────────┘
|
||||
```
|
||||
|
||||
## SHOW DICTIONARIES
|
||||
|
||||
Displays a list of [external dictionaries](dicts/external_dicts.md).
|
||||
|
||||
```sql
|
||||
SHOW DICTIONARIES [FROM <db>] [LIKE '<pattern>'] [LIMIT <N>] [INTO OUTFILE <filename>] [FORMAT <format>]
|
||||
```
|
||||
|
||||
If the `FROM` clause is not specified, the query returns the list of dictionaries from the current database.
|
||||
|
||||
You can get the same results as the `SHOW DICTIONARIES` query in the following way:
|
||||
|
||||
```sql
|
||||
SELECT name FROM system.dictionaries WHERE database = <db> [AND name LIKE <pattern>] [LIMIT <N>] [INTO OUTFILE <filename>] [FORMAT <format>]
|
||||
```
|
||||
|
||||
**Example**
|
||||
|
||||
The following query selects the first two rows from the list of tables in the `system` database, whose names contain `co`.
|
||||
|
||||
```sql
|
||||
SHOW DICTIONARIES FROM db LIKE '%reg%' LIMIT 2
|
||||
```
|
||||
```text
|
||||
┌─name─────────┐
|
||||
│ regions │
|
||||
│ region_names │
|
||||
└──────────────┘
|
||||
```
|
||||
|
||||
@ -248,3 +248,19 @@ SELECT a, b, c FROM (SELECT ...)
|
||||
没有单独的删除视图的语法。如果要删除视图，请使用`DROP TABLE`。
|
||||
|
||||
[来源文章](https://clickhouse.yandex/docs/en/query_language/create/) <!--hide-->
|
||||
|
||||
## CREATE DICTIONARY {#create-dictionary-query}
|
||||
|
||||
```sql
|
||||
CREATE DICTIONARY [IF NOT EXISTS] [db.]dictionary_name
|
||||
(
|
||||
key1 type1 [DEFAULT|EXPRESSION expr1] [HIERARCHICAL|INJECTIVE|IS_OBJECT_ID],
|
||||
key2 type2 [DEFAULT|EXPRESSION expr2] [HIERARCHICAL|INJECTIVE|IS_OBJECT_ID],
|
||||
attr1 type2 [DEFAULT|EXPRESSION expr3],
|
||||
attr2 type2 [DEFAULT|EXPRESSION expr4]
|
||||
)
|
||||
PRIMARY KEY key1, key2
|
||||
SOURCE(SOURCE_NAME([param1 value1 ... paramN valueN]))
|
||||
LAYOUT(LAYOUT_NAME([param_name param_value]))
|
||||
LIFETIME([MIN val1] MAX val2)
|
||||
```
|
||||
|
||||
Loading…
Reference in New Issue
Block a user