ClickHouse/docs/en/interfaces/mysql.md

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/en/interfaces/mysql	20	MySQL Interface

MySQL Interface

ClickHouse supports MySQL wire protocol. To enable the MySQL wire protocol, add the mysql_port setting to your server's configuration file. For example, you could define the port in a new XML file in your config.d folder:

<clickhouse>
    <mysql_port>9004</mysql_port>
</clickhouse>

Startup your ClickHouse server and look for a log message similar to the following that mentions Listening for MySQL compatibility protocol:

{} <Information> Application: Listening for MySQL compatibility protocol: 127.0.0.1:9004

Connect mysql to ClickHouse

The following command demonstrates how to connect the MySQL client mysql to ClickHouse:

mysql --protocol tcp -h [hostname] -u [username] -P [port_number] [database_name]

For example:

$ mysql --protocol tcp -h 127.0.0.1 -u default -P 9004 default

Output if a connection succeeded:

Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 4
Server version: 20.2.1.1-ClickHouse

Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql>

For compatibility with all MySQL clients, it is recommended to specify user password with double SHA1 in configuration file. If user password is specified using SHA256, some clients won’t be able to authenticate (mysqljs and old versions of command-line tool MySQL and MariaDB).

Restrictions:

• prepared queries are not supported

• some data types are sent as strings

To cancel a long query use KILL QUERY connection_id statement (it is replaced with KILL QUERY WHERE query_id = connection_id while proceeding). For example:

$ mysql --protocol tcp -h mysql_server -P 9004 default -u default --password=123 -e "KILL QUERY 123456;"

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