TDSQL for MySQL instances support read/write separation in the following modes:
A replica comment flag such as /*slave*/ can be added in a SQL statement, and the -c parameter is added after mysql to parse mysql -c -e "/*slave*/sql" to send the SQL statements to the replica server.
Note:
Comment flags including /*slave:slaveonly*/, /*slave:20*/, and /*slave:slaveonly,20*/ are also supported, where their values indicate the delay requirement that the replica server should satisfy, and slaveonly indicates that the query will not be sent to the source server if there is no eligible replica server.
//Read data from source//
select * from emp order by sal, deptno desc;
//Read data from replica//
/*slave*/ select * from emp order by sal, deptno desc;
Requests sent by read-only accounts are sent to the replica server based on the configured attributes.
