Issue Description
After a field is added to the MySQL instance, the system becomes lagged when executing the SQL statements.
Possible Causes
When a table field is added but the field is not indexed, if this field is referred to when executing the SQL statements, the lack of index causes a large amount of data which consumes a large number of CPU resources. As a result, the database becomes lagged.
Solution
It is recommended that you create indexes on the newly added fields and optimize slow SQL statements.