binary log

Recently we had the case that a customer claimed that MariaDB 10.3 Binary Log is using 150% more space on disk than MySQL 5.7 Binary Log. Because I never observed something similar, but to be honest, I did not look to intensively for this situation, we had to do some clarifications.

First we checked the usual variables which could be candidates for such a behaviour:

It is Saturday night at 23:19. Time to go to bed after a hard migration day. Just a last clean-up query before finishing: Tap tap tap. Enter! - Oops!

SQL> UPDATE prospect_lists_prospects SET prospect_list_id = '73ae6cca-7b34-c4a3-5500-5d0e2674dbb6';
Query OK, 4686 rows affected (0.21 sec)
Rows matched: 5666  Changed: 4686  Warnings: 0

A verification query to make sure I am in the mess:

From time to time we see in customer engagements that MySQL Master/Slave replication is set-up doing schema or table level replication filtering. This can be done either on Master or on Slave. If filtering is done on the Master (by the binlog_{do|ignore}_db settings), the binary log becomes incomplete and cannot be used for a proper Point-in-Time-Recovery. Therefore FromDual recommends AGAINST this approach.