Use this option to configure how the "Lock tables" feature works.
Yes: Use this option to set an easy way to lock tables. Just select the tables to be blocked in the "Block the following tables" dropdown and all those tables will be blocked.
No: Use this option to set your own tables. All INSERT, DELETE AND UPDATE queries against those tables won't be allowed, so USE THIS OPTION WITH CAUTION.
Take note that no changes will be allowed into users, group membership or content EVEN IF YOUR ACCOUNT IS A SUPER USER ACCOUNT:
Important: certain changes in users and content tables are allowed to avoid making the site unusable,as certain parameters are updated even visiting an article or when someone logs into the site. If you add other tables no update, delete or add operations won't be allowed.