# SELECT

```json metadata
{
  "title": "SELECT",
  "description": "Changes the selected database.",
  "categories": ["docs","develop","stack","oss","rs","rc","oss","kubernetes","clients"],
  "arguments": [{"display_text":"index","name":"index","type":"integer"}],
  "syntax_fmt": "SELECT index",
  "complexity": "O(1)",
  "group": "connection",
  "command_flags": ["loading","stale","fast"],
  "acl_categories": ["@fast","@connection"],
  "since": "1.0.0",
  "arity": 2,
  "tableOfContents": {"sections":[{"id":"redis-enterprise-and-redis-cloud-compatibility","title":"Redis Enterprise and Redis Cloud compatibility"},{"id":"return-information","title":"Return information"}]}
}
```













Select the Redis logical database having the specified zero-based numeric index.
New connections always use the database 0.

Selectable Redis databases are a form of namespacing: all databases are still persisted in the same RDB / AOF file. However different databases can have keys with the same name, and commands like [`FLUSHDB`](https://redis.io/docs/latest/commands/flushdb), [`SWAPDB`](https://redis.io/docs/latest/commands/swapdb) or [`RANDOMKEY`](https://redis.io/docs/latest/commands/randomkey) work on specific databases.

In practical terms, Redis databases should be used to separate different keys belonging to the same application (if needed), and not to use a single Redis instance for multiple unrelated applications.

When using Redis Cluster, the `SELECT` command cannot be used, since Redis Cluster only supports database zero. In the case of a Redis Cluster, having multiple databases would be useless and an unnecessary source of complexity. Commands operating atomically on a single database would not be possible with the Redis Cluster design and goals.

Since the currently selected database is a property of the connection, clients should track the currently selected database and re-select it on reconnection. While there is no command in order to query the selected database in the current connection, the [`CLIENT LIST`](https://redis.io/docs/latest/commands/client-list) output shows, for each client, the currently selected database.

## Redis Enterprise and Redis Cloud compatibility

| Redis<br />Enterprise | Redis<br />Cloud | <span style="min-width: 9em; display: table-cell">Notes</span> |
|:----------------------|:-----------------|:------|
| <span title="Not supported">&#x274c; Standard</span><br /><span title="Not supported"><nobr>&#x274c; Active-Active</nobr></span> | <span title="Not supported">&#x274c; Standard</span><br /><span title="Not supported"><nobr>&#x274c; Active-Active</nobr></span> | Redis Enterprise does not support shared databases due to potential negative performance impacts and blocks any related commands. The `SELECT` command is supported solely for compatibility with Redis Open Source but does not perform any operations in Redis Enterprise. |

## Return information

{{< multitabs id="select-return-info" 
    tab1="RESP2" 
    tab2="RESP3" >}}

[Simple string reply](../../develop/reference/protocol-spec#simple-strings): `OK`.

-tab-sep-

[Simple string reply](../../develop/reference/protocol-spec#simple-strings): `OK`.