ClickHouse/docs/en/sql-reference/statements/create/database.md

---
toc_priority: 35
toc_title: DATABASE
---

# CREATE DATABASE {#query-language-create-database}

Creates a new database.

``` sql
CREATE DATABASE [IF NOT EXISTS] db_name [ON CLUSTER cluster] [ENGINE = engine(...)] [COMMENT 'Comment']
```

## Clauses {#clauses}

### IF NOT EXISTS {#if-not-exists}

If the `db_name` database already exists, then ClickHouse does not create a new database and:

-   Doesn’t throw an exception if clause is specified.
-   Throws an exception if clause isn’t specified.

### ON CLUSTER {#on-cluster}

ClickHouse creates the `db_name` database on all the servers of a specified cluster. More details in a [Distributed DDL](../../../sql-reference/distributed-ddl.md) article.

### ENGINE {#engine}

By default, ClickHouse uses its own [Atomic](../../../engines/database-engines/atomic.md) database engine. There are also [Lazy](../../../engines/database-engines/lazy.md), [MySQL](../../../engines/database-engines/mysql.md), [PostgresSQL](../../../engines/database-engines/postgresql.md), [MaterializedMySQL](../../../engines/database-engines/materialized-mysql.md), [MaterializedPostgreSQL](../../../engines/database-engines/materialized-postgresql.md), [Replicated](../../../engines/database-engines/replicated.md), [SQLite](../../../engines/database-engines/sqlite.md).

### COMMENT {#comment}

You can add a comment to the database when you creating it.

The comment is supported for all database engines.

**Syntax**

``` sql
CREATE DATABASE db_name ENGINE = engine(...) COMMENT 'Comment'
```

**Example**

Query:

``` sql
CREATE DATABASE db_comment ENGINE = Memory COMMENT 'The temporary database';
SELECT name, comment FROM system.databases WHERE name = 'db_comment';
```

Result:

```text
┌─name───────┬─comment────────────────┐
│ db_comment │ The temporary database │
└────────────┴────────────────────────┘
```