title: Why I shouldn't use "Repeatable Read" with locking reading (select..for update)"?
body: <p>In the Mysql Document: "<a href="https://dev.mysql.com/doc/refman/5.7/en/innodb-deadlocks-handling.html" rel="noreferrer">https://dev.mysql.com/doc/refman/5.7/en/innodb-deadlocks-handling.html</a>"</p>
  
  <p>It mentioned: "<strong>If you use locking reads (SELECT ... FOR UPDATE or SELECT ... LOCK IN SHARE MODE), try using a lower isolation level such as READ COMMITTED.</strong>"</p>
  
  <p>Could someone tell me why I can't use "Repeatable Read"? Example will be good.</p>
  
  <p>Cheers</p>