Description and example usage of mysql Gap Lock

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1. When searching the scope, the entire range of data will be locked.

Even some data that does not exist in this range will be innocently locked. In some scenarios, it can have a great impact on performance.

2. If the execution condition is too large, InnoDB will lock all index key values in the entire range, which can easily affect performance.

Example

First change the value of field a to 1, 3, 5, 7, 9

Window A updates data in the range of a = 1x7

Update test_innodb_lock set bounded b5' where a > 1 and a