> ## Documentation Index
> Fetch the complete documentation index at: https://docs.tablepro.app/llms.txt
> Use this file to discover all available pages before exploring further.

# OceanBase

> Connect to an OceanBase MySQL-mode tenant through the bundled MySQL driver, directly or through OBProxy

The tenant goes in the user name: `root@test` on an observer's port 2881, `root@test#obcluster` through OBProxy on 2883. Any OceanBase version in MySQL mode connects. Host, password, SSH tunnels, SSL/TLS and `Cmd+K` database switching work as on [MySQL](/databases/mysql).

## Connection settings

| Field        | Default   | Notes                                                                                                             |
| ------------ | --------- | ----------------------------------------------------------------------------------------------------------------- |
| **Port**     | `2881`    | The observer's MySQL port. OBProxy listens on `2883`                                                              |
| **Username** | empty     | `user@tenant` on an observer, `user@tenant#cluster` through OBProxy. The sys tenant's administrator is `root@sys` |
| **Database** | empty     | Optional. Leave it empty to browse every database in the tenant                                                   |
| **SSL Mode** | Preferred | TLS first, plain text if the server refuses                                                                       |

**Release the Server Connection After** is available under Advanced. AWS IAM, Cloud SQL Auth Proxy and Unix socket are not offered; reach a private cluster through an [SSH tunnel](/connections/ssh-tunneling).

## Connection URL

```text theme={null}
oceanbase://root%40test:password@host:2881/database
oceanbase://root%40test%23obcluster:password@proxy-host:2883/database
```

Write the `@` in the user name as `%40` and the `#` as `%23`. `oceanbase+ssh://` opens it through an SSH tunnel. See [Connection URL Reference](/connections/urls).

## What differs from MySQL

* Connecting reads `@@version_comment`. A server that does not answer with `OceanBase` and a version number there is refused, so a wrong host or port fails at connect.
* The sidebar hides `information_schema`, `mysql`, `oceanbase`, `SYS`, `LBACSYS` and `ORAAUDITOR`. A tenant's `test` database stays listed.
* The [query timeout](/customization/general-settings#query-timeout) replaces OceanBase's own 10 second statement limit, and **No limit** removes it.
* CHECK constraints appear in the Structure tab on OceanBase 4.0 and later. Adding one from the Structure tab is not offered.
* Triggers appear in the Structure tab. Adding one from there is not offered.
* `EXPLAIN` shows the plan as text. `EXPLAIN FORMAT=JSON` and `EXPLAIN ANALYZE` are not offered.
* Table Maintenance offers `ANALYZE TABLE` on OceanBase 4.2.2 and later, and nothing on earlier versions.

A connection saved as **MySQL** that reaches an OceanBase server gets none of the above, because the MySQL handshake reports `5.7.25` or `5.6.25` and names no engine. Choose **OceanBase** as the connection type.

## Tables without a primary key

An OceanBase table declared without a primary key is edited as it is on MySQL: the `UPDATE` or `DELETE` matches every column of the row, and a save that would change more than one row, or none, stops and reports it. See [Change tracking](/features/change-tracking).

## Limitations

* Oracle-mode tenants do not connect. Point the connection at a MySQL-mode tenant.
* No Server Dashboard, and **File > Backup Dump…** stays dimmed.
* [Compare & Sync](/features/compare-sync) writes no structure script between OceanBase and MySQL or MariaDB. OceanBase against OceanBase works.
* Tenant and cluster administration is not offered. Create tenants with SQL as `root@sys`.

## Related

* [MySQL](/databases/mysql), for connection fields, SSL/TLS, and troubleshooting
* [TiDB](/databases/tidb)
* [SSH Tunneling](/connections/ssh-tunneling)