有时，我会在我的 PHP 错误日志中发现很多这些错误：
MYSQL.1213: Deadlock found when trying to get lock; try restarting transactionSQL
问题持续约 2 或 3 分钟。感谢stackoverflow，原因很容易找到：
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LATEST DETECTED DEADLOCK
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130320 15:53:37
*** (1) TRANSACTION:
TRANSACTION 0 83395751, ACTIVE 35 sec, process no 26405, OS thread id 140507872417536 starting index read
mysql tables in use 3, locked 3
LOCK WAIT 3 lock struct(s), heap size 1216, 2 row lock(s)
MySQL thread id 1163191, query id 199629038 localhost sosci Updating
UPDATE `database`.`table` SET `invalidate`='2013-03-21 03:53:02' …