参考 https://dev.mysql.com/doc/refman/8.0/en/innodb-locking.html MySQL各种锁0. 预备知识1. 行级锁1.1. 共享锁`Shared Locks` (`S`)1.2. 排他锁`Exclusive Locks`(`X`)1.3 共享锁和排它锁的冲突情况1.4 `共享锁`和`排他锁`用途2. 表级意向锁2.1. 意向共享锁 `Intention Shared Locks` (`IS`)2.2. 意向排他锁 `Intention Exc