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99 lines
3.0 KiB
Markdown
99 lines
3.0 KiB
Markdown
# SHOW Queries {#show-queries}
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## SHOW CREATE TABLE {#show-create-table}
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``` sql
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SHOW CREATE [TEMPORARY] [TABLE|DICTIONARY] [db.]table [INTO OUTFILE filename] [FORMAT format]
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```
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Returns a single `String`-type ‘statement’ column, which contains a single value – the `CREATE` query used for creating the specified object.
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## SHOW DATABASES {#show-databases}
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``` sql
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SHOW DATABASES [INTO OUTFILE filename] [FORMAT format]
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```
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Prints a list of all databases.
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This query is identical to `SELECT name FROM system.databases [INTO OUTFILE filename] [FORMAT format]`.
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## SHOW PROCESSLIST {#show-processlist}
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``` sql
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SHOW PROCESSLIST [INTO OUTFILE filename] [FORMAT format]
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```
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Outputs the content of the [system.processes](../operations/system_tables.md#system_tables-processes) table, that contains a list of queries that is being processed at the moment, excepting `SHOW PROCESSLIST` queries.
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The `SELECT * FROM system.processes` query returns data about all the current queries.
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Tip (execute in the console):
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``` bash
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$ watch -n1 "clickhouse-client --query='SHOW PROCESSLIST'"
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```
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## SHOW TABLES {#show-tables}
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Displays a list of tables.
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``` sql
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SHOW [TEMPORARY] TABLES [{FROM | IN} <db>] [LIKE '<pattern>' | WHERE expr] [LIMIT <N>] [INTO OUTFILE <filename>] [FORMAT <format>]
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```
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If the `FROM` clause is not specified, the query returns the list of tables from the current database.
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You can get the same results as the `SHOW TABLES` query in the following way:
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``` sql
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SELECT name FROM system.tables WHERE database = <db> [AND name LIKE <pattern>] [LIMIT <N>] [INTO OUTFILE <filename>] [FORMAT <format>]
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```
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**Example**
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The following query selects the first two rows from the list of tables in the `system` database, whose names contain `co`.
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``` sql
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SHOW TABLES FROM system LIKE '%co%' LIMIT 2
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```
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``` text
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┌─name───────────────────────────┐
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│ aggregate_function_combinators │
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│ collations │
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└────────────────────────────────┘
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```
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## SHOW DICTIONARIES {#show-dictionaries}
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Displays a list of [external dictionaries](dicts/external_dicts.md).
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``` sql
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SHOW DICTIONARIES [FROM <db>] [LIKE '<pattern>'] [LIMIT <N>] [INTO OUTFILE <filename>] [FORMAT <format>]
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```
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If the `FROM` clause is not specified, the query returns the list of dictionaries from the current database.
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You can get the same results as the `SHOW DICTIONARIES` query in the following way:
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``` sql
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SELECT name FROM system.dictionaries WHERE database = <db> [AND name LIKE <pattern>] [LIMIT <N>] [INTO OUTFILE <filename>] [FORMAT <format>]
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```
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**Example**
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The following query selects the first two rows from the list of tables in the `system` database, whose names contain `reg`.
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``` sql
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SHOW DICTIONARIES FROM db LIKE '%reg%' LIMIT 2
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```
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``` text
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┌─name─────────┐
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│ regions │
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│ region_names │
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└──────────────┘
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```
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[Original article](https://clickhouse.tech/docs/en/query_language/show/) <!--hide-->
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