mysql> SELECT * FROM t WHERE i = 2 FOR UPDATE NOWAIT; ERROR 3572 (HY000): Statement aborted because lock(s) could not be acquired immediately and NOWAIT is set. 从这里可以看到在 for update nowait 直接执行返回,从错误提示上可以出来因为设置了 nowait 因为获取不到锁直接退出了。# Session 2...
select … for update，select … for share(8.0新增语法) 添加 NOWAIT、SKIP LOCKED语法，跳过锁等待...
ON rl.ENGINE_LOCK_ID = w.REQUESTING_ENGINE_LOCK_ID ORDER BY r.trx_wait_started 5.7 中 sys.innodb_lock_waits 涉及 3 个基表: information_schema.innodb_lock_waits information_schema.innodb_locks information_schema.innodb_trx 8.0 中 sys.innodb_lock_waits 也涉及 3 个基表: performance_schema.d...
MySQL8才有的特性,5.7会报错:You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'skip locked' at line 1。 nowait 官方文档:https://dev.mysql.com/doc/refman/8.0/en/innodb-locking-reads.html#innodb-locking-...
对于select ... for share(8.0新增加查询共享锁的语法)或 select ... for update, 在语句后面添加NOWAIT、SKIP LOCKED语法可以跳过锁等待,或者跳过锁定。 在5.7及之前的版本,select...for update,如果获取不到锁,会一直等待,直到innodb_lock_wait_timeout超时。
| wait | 321 | --等待事件 | statement | 193 | --语句执行的信息 | stage | 129 | --语句执行阶段的时间统计 | idle | 1 | --空闲 | transaction | 1 | +---+---+ 6 rows in set (0.00 sec) --4、查看监控的对象, 默认对mysql、performance_schema、...
ORDER BY r.trx_wait_started 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. MySQL 8.0 中简化的视图定义 CREATE VIEW sys.innodb_lock_waits (...) AS SELECT ... FROM performance_schema.data_lock_waits w JOIN information_schema.INNODB_TRX b ...
CREATEVIEWsys.innodb_lock_waitsASSELECT...FROMinformation_schema.innodb_lock_waits wJOINinformation_schema.innodb_trx bONb.trx_id=w.blocking_trx_idJOINinformation_schema.innodb_trx rONr.trx_id=w.requesting_trx_idJOINinformation_schema.innodb_locks blONbl.lock_id=w.blocking_lock_idJOINinformation_...
1.15-innodb select for update跳过锁等待 select … for update,select … for share(8.0新增语法) 添加 NOWAIT、SKIP LOCKED语法,跳过锁等待,或者跳过锁定。 在5.7及之前的版本,select…for update,如果获取不到锁,会一直等待,直到innodb_lock_wait_timeout超时。