这个InnoDB僵局真的让我拉扯我的头发。据我所见：
交易（1）正在等待“申请”上的PRIMARY
后者已被（2）获得了一些相当长时间运行的更新（SELECT * FROM应用程序WHERE ID = xxxx FOR UPDATE）
到目前为止，非常好 - 人们会期望（1）等待锁定，然后继续工作。
但是，一旦（2）准备好保存它的工作（并提交事务），它就会因为某种原因（1）设法锁定某些二级索引而失败并出现死锁。 如果PRIMARY由（2）持有，地狱如何（1）设法获得任何锁定。
可以预期，如果（2）最初获得了主锁（SELECT * FROM应用程序WHERE ID = xxxx FOR UPDATE），它也会在所有二级索引上设置锁。如果tasked == NULL，它是否有可能不会锁定“任务”索引，从而允许（1）在对PRIMARY进行锁定之前获取对“任务”的锁定？
我没有运气复制这种情况..
谢谢！
劳里
------------------------
LATEST DETECTED DEADLOCK
------------------------
130428 17:04:06
*** (1) TRANSACTION:
TRANSACTION A369A8C, ACTIVE 1 sec fetching rows
mysql tables in use 3, locked 3
LOCK WAIT 217 lock struct(s), heap size 31160, 636 row lock(s)
MySQL thread id 13310554, OS thread handle 0x7f06cc2d7700, query id 177699568 217.146.78.151 shard67 Sending data
SELECT `applications`.* FROM `applications`
LEFT JOIN `applicants` ON applicants.ID = applications.applicant_ID
LEFT JOIN `regions` ON regions.ID = applicants.region_ID WHERE (status <> 'Blank') AND (status <> 'Closed') AND (revised < 1367154245) AND (tasked IS NULL OR tasked < 1367147045) AND (commence_year >= '2013') AND (regions.instance_ID = '1') ORDER BY `tasked` ASC, `ID` ASC LIMIT 20 FOR UPDATE
*** (1) WAITING FOR THIS LOCK TO BE GRANTED:
RECORD LOCKS space id 20021 page no 1192 n bits 80 index `PRIMARY` of table `dream-shard67`.`applications` trx id A369A8C lock_mode X locks rec but not gap waiting
*** (2) TRANSACTION:
TRANSACTION A369A87, ACTIVE 1 sec updating or deleting
mysql tables in use 1, locked 1
16 lock struct(s), heap size 3112, 22 row lock(s), undo log entries 5
MySQL thread id 13310563, OS thread handle 0x7f06cc151700, query id 177699599 217.146.76.127 shard67
UPDATE `applications` SET `revised` = '1367157846', `tasked` = '1367157846', `revision_ID` = '140649', `xml` = 'Zms6\noMmI$%[v....snipped binary data
*** (2) HOLDS THE LOCK(S):
RECORD LOCKS space id 20021 page no 1192 n bits 72 index `PRIMARY` of table `dream-shard67`.`applications` trx id A369A87 lock_mode X locks rec but not gap
*** (2) WAITING FOR THIS LOCK TO BE GRANTED:
RECORD LOCKS space id 20021 page no 292 n bits 1280 index `tasked` of table `dream-shard67`.`applications` trx id A369A87 lock_mode X locks rec but not gap waiting
*** WE ROLL BACK TRANSACTION (2)