What Is Gap Lock in Mysql
A Gap Lock Is a Lock on a Gap Between Index Records, or a Lock on the Gap Before the First or After the Last Index Record. for Example, Select C1 from T Where...
A gap lock is a lock on a gap between index records, or a lock on the gap before the first or after the last index record. For example, SELECT c1 FROM t WHERE c1 BETWEEN 10 and 20 FOR UPDATE; prevents other transactions from inserting a value of 15 into column t.
What is Gap lock MySQL?
A gap lock is a lock on a gap between index records, or a lock on the gap before the first or after the last index record. For example, SELECT c1 FROM t WHERE c1 BETWEEN 10 and 20 FOR UPDATE; prevents other transactions from inserting a value of 15 into column t.
What is exclusive lock in MySQL?
Exclusive locks are described in MySQL glossary: A kind of lock that prevents any other transaction from locking the same row. Depending on the transaction isolation level, this kind of lock might block other transactions from writing to the same row, or might also block other transactions from reading the same row.