ClickHouse/docs/en/query_language/show.md
2020-03-20 13:10:48 +03:00

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# SHOW Queries {#show-queries}
## SHOW CREATE TABLE {#show-create-table}
``` sql
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 object.
## SHOW DATABASES {#show-databases}
``` sql
SHOW DATABASES [INTO OUTFILE filename] [FORMAT format]
```
Prints a list of all databases.
This query is identical to `SELECT name FROM system.databases [INTO OUTFILE filename] [FORMAT format]`.
## SHOW PROCESSLIST {#show-processlist}
``` sql
SHOW PROCESSLIST [INTO OUTFILE filename] [FORMAT format]
```
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.
The `SELECT * FROM system.processes` query returns data about all the current queries.
Tip (execute in the console):
``` bash
$ watch -n1 "clickhouse-client --query='SHOW PROCESSLIST'"
```
## SHOW TABLES {#show-tables}
Displays a list of tables.
``` sql
SHOW [TEMPORARY] TABLES [{FROM | IN} <db>] [LIKE '<pattern>' | WHERE expr] [LIMIT <N>] [INTO OUTFILE <filename>] [FORMAT <format>]
```
If the `FROM` clause is not specified, the query returns the list of tables from the current database.
You can get the same results as the `SHOW TABLES` query in the following way:
``` sql
SELECT name FROM system.tables 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 TABLES FROM system LIKE '%co%' LIMIT 2
```
``` text
┌─name───────────────────────────┐
│ aggregate_function_combinators │
│ collations │
└────────────────────────────────┘
```
## SHOW DICTIONARIES {#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 `reg`.
``` sql
SHOW DICTIONARIES FROM db LIKE '%reg%' LIMIT 2
```
``` text
┌─name─────────┐
│ regions │
│ region_names │
└──────────────┘
```
[Original article](https://clickhouse.tech/docs/en/query_language/show/) <!--hide-->