ClickHouse/docs/en/sql-reference/statements/show.md
Ivan Blinkov 7170f3c534
[docs] split aggregate function and system table references (#11742)
* prefer relative links from root

* wip

* split aggregate function reference

* split system tables
2020-06-18 11:24:31 +03:00

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---
toc_priority: 38
toc_title: SHOW
---
# 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/processes.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](../../sql-reference/dictionaries/external-dictionaries/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 │
└──────────────┘
```
## SHOW GRANTS {#show-grants-statement}
Shows privileges for a user.
### Syntax {#show-grants-syntax}
``` sql
SHOW GRANTS [FOR user]
```
If user is not specified, the query returns privileges for the current user.
## SHOW CREATE USER {#show-create-user-statement}
Shows parameters that were used at a [user creation](../../sql-reference/statements/create.md#create-user-statement).
`SHOW CREATE USER` doesnt output user passwords.
### Syntax {#show-create-user-syntax}
``` sql
SHOW CREATE USER [name | CURRENT_USER]
```
## SHOW CREATE ROLE {#show-create-role-statement}
Shows parameters that were used at a [role creation](../../sql-reference/statements/create.md#create-role-statement).
### Syntax {#show-create-role-syntax}
``` sql
SHOW CREATE ROLE name
```
## SHOW CREATE ROW POLICY {#show-create-row-policy-statement}
Shows parameters that were used at a [row policy creation](../../sql-reference/statements/create.md#create-row-policy-statement).
### Syntax {#show-create-row-policy-syntax}
``` sql
SHOW CREATE [ROW] POLICY name ON [database.]table
```
## SHOW CREATE QUOTA {#show-create-quota-statement}
Shows parameters that were used at a [quota creation](../../sql-reference/statements/create.md#create-quota-statement).
### Syntax {#show-create-row-policy-syntax}
``` sql
SHOW CREATE QUOTA [name | CURRENT]
```
## SHOW CREATE SETTINGS PROFILE {#show-create-settings-profile-statement}
Shows parameters that were used at a [settings profile creation](../../sql-reference/statements/create.md#create-settings-profile-statement).
### Syntax {#show-create-row-policy-syntax}
``` sql
SHOW CREATE [SETTINGS] PROFILE name
```
[Original article](https://clickhouse.tech/docs/en/query_language/show/) <!--hide-->