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---
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slug: /en/sql-reference/statements/show
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sidebar_position: 37
sidebar_label: SHOW
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---
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# SHOW Statements
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## SHOW CREATE TABLE | DICTIONARY | VIEW | DATABASE
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``` sql
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SHOW [CREATE] [TEMPORARY] TABLE|DICTIONARY|VIEW|DATABASE [db.]table|view [INTO OUTFILE filename] [FORMAT format]
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```
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Returns a single column of type String containing the CREATE query used for creating the specified object.
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`SHOW TABLE t` and `SHOW DATABASE db` have the same meaning as `SHOW CREATE TABLE|DATABASE t|db` , but `SHOW t` and `SHOW db` are not supported.
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Note that if you use this statement to get `CREATE` query of system tables, you will get a *fake* query, which only declares table structure, but cannot be used to create table.
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## SHOW DATABASES
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Prints a list of all databases.
```sql
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SHOW DATABASES [[NOT] LIKE | ILIKE '< pattern > '] [LIMIT < N > ] [INTO OUTFILE filename] [FORMAT format]
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```
This statement is identical to the query:
```sql
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SELECT name FROM system.databases [WHERE name [NOT] LIKE | ILIKE '< pattern > '] [LIMIT < N > ] [INTO OUTFILE filename] [FORMAT format]
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```
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**Examples**
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Getting database names, containing the symbols sequence 'de' in their names:
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``` sql
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SHOW DATABASES LIKE '%de%'
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```
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Result:
``` text
┌─name────┐
│ default │
└─────────┘
```
Getting database names, containing symbols sequence 'de' in their names, in the case insensitive manner:
``` sql
SHOW DATABASES ILIKE '%DE%'
```
Result:
``` text
┌─name────┐
│ default │
└─────────┘
```
Getting database names, not containing the symbols sequence 'de' in their names:
``` sql
SHOW DATABASES NOT LIKE '%de%'
```
Result:
``` text
┌─name───────────────────────────┐
│ _temporary_and_external_tables │
│ system │
│ test │
│ tutorial │
└────────────────────────────────┘
```
Getting the first two rows from database names:
``` sql
SHOW DATABASES LIMIT 2
```
Result:
``` text
┌─name───────────────────────────┐
│ _temporary_and_external_tables │
│ default │
└────────────────────────────────┘
```
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**See also**
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- [CREATE DATABASE ](https://clickhouse.com/docs/en/sql-reference/statements/create/database/#query-language-create-database )
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## SHOW PROCESSLIST
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``` sql
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SHOW PROCESSLIST [INTO OUTFILE filename] [FORMAT format]
```
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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.
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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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## SHOW TABLES
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Displays a list of tables.
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```sql
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SHOW [FULL] [TEMPORARY] TABLES [{FROM | IN} < db > ] [[NOT] LIKE | ILIKE '< pattern > '] [LIMIT < N > ] [INTO OUTFILE < filename > ] [FORMAT < format > ]
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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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This statement is identical to the query:
```sql
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SELECT name FROM system.tables [WHERE name [NOT] LIKE | ILIKE '< pattern > '] [LIMIT < N > ] [INTO OUTFILE < filename > ] [FORMAT < format > ]
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```
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**Examples**
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Getting table names, containing the symbols sequence 'user' in their names:
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``` sql
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SHOW TABLES FROM system LIKE '%user%'
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```
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Result:
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``` text
┌─name─────────────┐
│ user_directories │
│ users │
└──────────────────┘
```
Getting table names, containing sequence 'user' in their names, in the case insensitive manner:
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``` sql
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SHOW TABLES FROM system ILIKE '%USER%'
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```
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Result:
``` text
┌─name─────────────┐
│ user_directories │
│ users │
└──────────────────┘
```
Getting table names, not containing the symbol sequence 's' in their names:
``` sql
SHOW TABLES FROM system NOT LIKE '%s%'
```
Result:
``` text
┌─name─────────┐
│ metric_log │
│ metric_log_0 │
│ metric_log_1 │
└──────────────┘
```
Getting the first two rows from table names:
``` sql
SHOW TABLES FROM system LIMIT 2
```
Result:
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``` text
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┌─name───────────────────────────┐
│ aggregate_function_combinators │
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│ asynchronous_metric_log │
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└────────────────────────────────┘
```
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**See also**
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- [Create Tables ](https://clickhouse.com/docs/en/getting-started/tutorial/#create-tables )
- [SHOW CREATE TABLE ](https://clickhouse.com/docs/en/sql-reference/statements/show/#show-create-table )
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## SHOW COLUMNS
Displays a list of columns
```sql
SHOW [EXTENDED] [FULL] COLUMNS {FROM | IN} < table > [{FROM | IN} < db > ] [{[NOT] {LIKE | ILIKE} '< pattern > ' | WHERE < expr > }] [LIMIT < N > ] [INTO
OUTFILE < filename > ] [FORMAT < format > ]
```
The database and table name can be specified in abbreviated form as `<db>.<table>` , i.e. `FROM tab FROM db` and `FROM db.tab` are
equivalent. If no database is specified, the query returns the list of columns from the current database.
The optional keyword `EXTENDED` currently has no effect, it only exists for MySQL compatibility.
The optional keyword `FULL` causes the output to include the collation, comment and privilege columns.
`SHOW COLUMNS` produces a result table with the following structure:
- field - The name of the column (String)
- type - The column data type (String)
- null - If the column data type is Nullable (UInt8)
- key - `PRI` if the column is part of the primary key, `SOR` if the column is part of the sorting key, empty otherwise (String)
- default - Default expression of the column if it is of type `ALIAS` , `DEFAULT` , or `MATERIALIZED` , otherwise `NULL` . (Nullable(String))
- extra - Additional information, currently unused (String)
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- collation - (only if `FULL` keyword was specified) Collation of the column, always `NULL` because ClickHouse has no per-column collations (Nullable(String))
- comment - (only if `FULL` keyword was specified) Comment on the column (String)
- privilege - (only if `FULL` keyword was specified) The privilege you have on this column, currently not available (String)
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**Examples**
Getting information about all columns in table 'order' starting with 'delivery_':
```sql
SHOW COLUMNS FROM 'orders' LIKE 'delivery_%'
```
Result:
``` text
┌─field───────────┬─type─────┬─null─┬─key─────┬─default─┬─extra─┐
│ delivery_date │ DateTime │ 0 │ PRI SOR │ ᴺᵁᴸᴸ │ │
│ delivery_status │ Bool │ 0 │ │ ᴺᵁᴸᴸ │ │
└─────────────────┴──────────┴──────┴─────────┴─────────┴───────┘
```
**See also**
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- [system.columns ](https://clickhouse.com/docs/en/operations/system-tables/columns )
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## SHOW DICTIONARIES
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Displays a list of [Dictionaries ](../../sql-reference/dictionaries/index.md ).
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``` sql
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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:
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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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**Examples**
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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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``` text
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┌─name─────────┐
│ regions │
│ region_names │
└──────────────┘
```
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## SHOW GRANTS
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Shows privileges for a user.
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**Syntax**
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``` sql
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SHOW GRANTS [FOR user1 [, user2 ...]]
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```
If user is not specified, the query returns privileges for the current user.
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## SHOW CREATE USER
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Shows parameters that were used at a [user creation ](../../sql-reference/statements/create/user.md ).
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`SHOW CREATE USER` does not output user passwords.
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**Syntax**
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``` sql
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SHOW CREATE USER [name1 [, name2 ...] | CURRENT_USER]
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```
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## SHOW CREATE ROLE
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Shows parameters that were used at a [role creation ](../../sql-reference/statements/create/role.md ).
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**Syntax**
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``` sql
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SHOW CREATE ROLE name1 [, name2 ...]
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```
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## SHOW CREATE ROW POLICY
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Shows parameters that were used at a [row policy creation ](../../sql-reference/statements/create/row-policy.md ).
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**Syntax**
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``` sql
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SHOW CREATE [ROW] POLICY name ON [database1.]table1 [, [database2.]table2 ...]
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```
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## SHOW CREATE QUOTA
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Shows parameters that were used at a [quota creation ](../../sql-reference/statements/create/quota.md ).
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**Syntax**
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``` sql
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SHOW CREATE QUOTA [name1 [, name2 ...] | CURRENT]
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```
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## SHOW CREATE SETTINGS PROFILE
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Shows parameters that were used at a [settings profile creation ](../../sql-reference/statements/create/settings-profile.md ).
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**Syntax**
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``` sql
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SHOW CREATE [SETTINGS] PROFILE name1 [, name2 ...]
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```
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## SHOW USERS
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Returns a list of [user account ](../../guides/sre/user-management/index.md#user-account-management ) names. To view user accounts parameters, see the system table [system.users ](../../operations/system-tables/users.md#system_tables-users ).
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**Syntax**
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``` sql
SHOW USERS
```
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## SHOW ROLES
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Returns a list of [roles ](../../guides/sre/user-management/index.md#role-management ). To view another parameters, see system tables [system.roles ](../../operations/system-tables/roles.md#system_tables-roles ) and [system.role_grants ](../../operations/system-tables/role-grants.md#system_tables-role_grants ).
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**Syntax**
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``` sql
SHOW [CURRENT|ENABLED] ROLES
```
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## SHOW PROFILES
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Returns a list of [setting profiles ](../../guides/sre/user-management/index.md#settings-profiles-management ). To view user accounts parameters, see the system table [settings_profiles ](../../operations/system-tables/settings_profiles.md#system_tables-settings_profiles ).
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**Syntax**
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``` sql
SHOW [SETTINGS] PROFILES
```
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## SHOW POLICIES
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Returns a list of [row policies ](../../guides/sre/user-management/index.md#row-policy-management ) for the specified table. To view user accounts parameters, see the system table [system.row_policies ](../../operations/system-tables/row_policies.md#system_tables-row_policies ).
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**Syntax**
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``` sql
SHOW [ROW] POLICIES [ON [db.]table]
```
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## SHOW QUOTAS
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Returns a list of [quotas ](../../guides/sre/user-management/index.md#quotas-management ). To view quotas parameters, see the system table [system.quotas ](../../operations/system-tables/quotas.md#system_tables-quotas ).
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**Syntax**
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``` sql
SHOW QUOTAS
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```
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## SHOW QUOTA
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Returns a [quota ](../../operations/quotas.md ) consumption for all users or for current user. To view another parameters, see system tables [system.quotas_usage ](../../operations/system-tables/quotas_usage.md#system_tables-quotas_usage ) and [system.quota_usage ](../../operations/system-tables/quota_usage.md#system_tables-quota_usage ).
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**Syntax**
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``` sql
SHOW [CURRENT] QUOTA
```
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## SHOW ACCESS
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Shows all [users ](../../guides/sre/user-management/index.md#user-account-management ), [roles ](../../guides/sre/user-management/index.md#role-management ), [profiles ](../../guides/sre/user-management/index.md#settings-profiles-management ), etc. and all their [grants ](../../sql-reference/statements/grant.md#grant-privileges ).
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**Syntax**
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``` sql
SHOW ACCESS
```
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## SHOW CLUSTER(s)
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Returns a list of clusters. All available clusters are listed in the [system.clusters ](../../operations/system-tables/clusters.md ) table.
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:::note
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`SHOW CLUSTER name` query displays the contents of system.clusters table for this cluster.
:::
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**Syntax**
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``` sql
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SHOW CLUSTER '< name > '
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SHOW CLUSTERS [[NOT] LIKE|ILIKE '< pattern > '] [LIMIT < N > ]
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```
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**Examples**
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Query:
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``` sql
SHOW CLUSTERS;
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```
Result:
```text
┌─cluster──────────────────────────────────────┐
│ test_cluster_two_shards │
│ test_cluster_two_shards_internal_replication │
│ test_cluster_two_shards_localhost │
│ test_shard_localhost │
│ test_shard_localhost_secure │
│ test_unavailable_shard │
└──────────────────────────────────────────────┘
```
Query:
``` sql
SHOW CLUSTERS LIKE 'test%' LIMIT 1;
```
Result:
```text
┌─cluster─────────────────┐
│ test_cluster_two_shards │
└─────────────────────────┘
```
Query:
``` sql
SHOW CLUSTER 'test_shard_localhost' FORMAT Vertical;
```
Result:
```text
Row 1:
──────
cluster: test_shard_localhost
shard_num: 1
shard_weight: 1
replica_num: 1
host_name: localhost
host_address: 127.0.0.1
port: 9000
is_local: 1
user: default
default_database:
errors_count: 0
estimated_recovery_time: 0
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```
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## SHOW SETTINGS
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Returns a list of system settings and their values. Selects data from the [system.settings ](../../operations/system-tables/settings.md ) table.
**Syntax**
```sql
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SHOW [CHANGED] SETTINGS LIKE|ILIKE < name >
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```
**Clauses**
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`LIKE|ILIKE` allow to specify a matching pattern for the setting name. It can contain globs such as `%` or `_` . `LIKE` clause is case-sensitive, `ILIKE` — case insensitive.
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When the `CHANGED` clause is used, the query returns only settings changed from their default values.
**Examples**
Query with the `LIKE` clause:
```sql
SHOW SETTINGS LIKE 'send_timeout';
```
Result:
```text
┌─name─────────┬─type────┬─value─┐
│ send_timeout │ Seconds │ 300 │
└──────────────┴─────────┴───────┘
```
Query with the `ILIKE` clause:
```sql
SHOW SETTINGS ILIKE '%CONNECT_timeout%'
```
Result:
```text
┌─name────────────────────────────────────┬─type─────────┬─value─┐
│ connect_timeout │ Seconds │ 10 │
│ connect_timeout_with_failover_ms │ Milliseconds │ 50 │
│ connect_timeout_with_failover_secure_ms │ Milliseconds │ 100 │
└─────────────────────────────────────────┴──────────────┴───────┘
```
Query with the `CHANGED` clause:
```sql
SHOW CHANGED SETTINGS ILIKE '%MEMORY%'
```
Result:
```text
┌─name─────────────┬─type───┬─value───────┐
│ max_memory_usage │ UInt64 │ 10000000000 │
└──────────────────┴────────┴─────────────┘
```
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## SHOW FILESYSTEM CACHES
```sql
SHOW FILESYSTEM CACHES
```
Result:
``` text
┌─Caches────┐
│ s3_cache │
└───────────┘
```
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**See Also**
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- [system.settings ](../../operations/system-tables/settings.md ) table
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## SHOW ENGINES
``` sql
SHOW ENGINES [INTO OUTFILE filename] [FORMAT format]
```
Outputs the content of the [system.table_engines ](../../operations/system-tables/table_engines.md ) table, that contains description of table engines supported by server and their feature support information.
**See Also**
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- [system.table_engines ](../../operations/system-tables/table_engines.md ) table