MySQL Common status

Reference "MySQL database development, optimization and management Maintenance", the main purpose is to remember important content and study notes

Query status statement: Show [Session|global] status, default is session.

Com_xxx represents the number of executions per xxx, usually related to several statistical parameters:

1. Com_select: The number of times a select operation is performed, only one query is incremented by 1;
2. Com_insert: The number of times the insert operation is performed, and the insert operation for bulk inserts is incremented only once;
3. Com_update: The number of times the update operation was performed (count of executions, so both commits and rollbacks are counted);
4. Com_delete: The number of times the delete operation was performed;
5. Com_commit: Transaction commit times
6. Com_rollback: Transaction rollback number (if there are too many database rollbacks, there may be a transaction or code writing problem)

The above statistics all engine table operation record, if only see the InnoDB Storage engine table, see the following parameters:

Innodb_rows_read, innodb_rows_inserted, innodb_rows_updated, innodb_rows_deleted.

MySQL Common status