TiDB Controller User Guide

TiDB Controller is a command line tool of TiDB, usually used to obtain the status information of TiDB for debugging.

Compile from source code

  • Compilation environment requirement: Go Version 1.7 or later
  • Compilation procedures: Go to the root directory of the TiDB Controller project, use the make command to compile, and generate tidb-ctl.
  • Compilation documentation: you can find the help files in the doc directory; if the help files are lost or you want to update them, use the make doc command to generate the help files.

Usage introduction

The usage of tidb-ctl consists of command (including subcommand), option, and flag.

  • command: characters without - or --
  • option: characters with - or --
  • flag: characters exactly following the command or option, passing value to the command or option

Usage example: tidb-ctl schema in mysql -n db

  • schema: the command
  • in: the subcommand of schema
  • mysql: the flag of in
  • -n: the option
  • db: the flag of -n

Get help

Use tidb-ctl -h/--help to get the help information. tidb-ctl consists of multiple layers of commands. You can use -h/--help to get the help information of tidb-ctl and all other subcommands.

Connect

tidb-ctl -H/--host {TiDB service address} -P/--port {TiDB service port}

If you do not add an address or a port, the default value is used. The default address is 127.0.0.1 (service address must be the IP address); the default port is 10080. Connection options are top-level options and apply to all of the following commands.

Currently, TiDB Controller can obtain four categories of information using the following four commands:

  • tidb-ctl mvcc: MVCC information
  • tidb-ctl region: Region information
  • tidb-ctl schema: Schema information
  • tidb-ctl table: Table information

Examples

The following example shows how to obtain the schema information:

Use tidb-ctl schema -h to get the help information of the subcommands. schema has two subcommands: in and tid.

  • in is used to obtain the table schema of all tables in the database through the database name.
  • tid is used to obtain the table schema through the unique table_id in the whole database.

The in command

You can also use tidb-ctl schema in -h/--help to get the help information of the in subcommand.

Basic usage
tidb-ctl schema in {database name}

For example, tidb-ctl schema in mysql returns the following result:

[
    {
        "id": 13,
        "name": {
            "O": "columns_priv",
            "L": "columns_priv"
        },
              ...
        "update_timestamp": 399494726837600268,
        "ShardRowIDBits": 0,
        "Partition": null
    }
]

The result is long and displayed in JSON. The above result is a truncated one.

  • If you want to specify the table name, use tidb-ctl schema in {database} -n {table name} to filter.

    For example, tidb-ctl schema in mysql -n db returns the table schema of the db table in the mysql database:

    {
        "id": 9,
        "name": {
            "O": "db",
            "L": "db"
        },
        ...
        "Partition": null
    }
    

    The above result is a truncated one, too.

  • If you want to specify the server address, use the -H -P option.

    For example, tidb-ctl -H 127.0.0.1 -P 10080 schema in mysql -n db.