[Level 2] Enhance the performance with MySQL checksum table with MyISAM engine.

You can create MyISAM table with the option "checksum=1", to let MyISAM table store the checksum value. Otherwise, checksum table, will need to do a full table scan.
PS. This only support on MyISAM engine.

mysql> create table t (id int) engine=MyISAM checksum=1;
mysql> checksum table t;

Wish this helps.

regards,
Stanley Huang
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