v.21.3Improvement
MYSQL_OPT_RECONNECT Option Control via Config Parameter in MySQL Replica
The value of MYSQL_OPT_RECONNECT option can now be controlled by "opt_reconnect" parameter in the config section of mysql replica. #19998 (Alexander Kazakov).
Why it matters
This feature allows users to explicitly enable or disable the automatic reconnection behavior for MySQL replicas in ClickHouse. It provides better control over replica connection handling, improving stability and configurability when working with MySQL data sources.How to use it
To use this feature, add theopt_reconnect parameter to the MySQL replica configuration section in the ClickHouse configuration file and set it to true or false depending on whether you want automatic reconnection enabled or disabled.