What Is a Dead Lock in MySQL

Q

What Is a Dead Lock in MySQL?

✍: FYIcenter.com

A

A dead lock is phenomenon happens between two transactions with each of them holding a lock that blocks the other transaction as shown in the following diagram:

(transaction 1)                    (transaction 2)
update row X to create lock 1
                                  update row Y to create lock 2
                                  update row X
                                  (blocked by lock 1)
update row Y
(blocked by lock 2)

(dead lock created)

⇒ Experiment with Dead Locks in MySQL

⇐ Error: Lock Wait Timeout Exceeded in MySQL

⇑ Transaction Management: Commit or Rollback in MySQL

⇑⇑ MySQL Database Tutorials

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Error: Lock Wait Timeout Exceeded in MySQL
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Locks, Timeouts, and Deadlocks in MySQL
What Are Impacts on Applications from Locks, Timeouts, and DeadLocks in MySQL? If you are using transactions with REPEATABLE READ isolation level and transaction safe storage engines in your applications, data locks, lock timeouts, and dead lock detections will impact your application in a concurren... 2017-07-21, 2759🔥, 0💬

What Is a Data Lock in MySQL
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What Is MySQL
What Is MySQL? MySQL is an open source database management system developed by MySQL AB, http://www.mysql.com. ⇒ What Is mSQL in MySQL ⇐ Database Basics and Terminologies in MySQL ⇑ Database Basics and Terminologies in MySQL ⇑⇑ MySQL Database Tutorials 2017-07-21, 1827🔥, 0💬

What Is a Dead Lock in MySQL
What Is a Dead Lock in MySQL? A dead lock is phenomenon happens between two transactions with each of them holding a lock that blocks the other transaction as shown in the following diagram: (transaction 1) (transaction 2) update row X to create lock 1 update row Y to create lock 2 update row X (blo... 2017-04-28, 1821🔥, 0💬

Transaction Waiting for a Data Lock in MySQL
How Long a Transaction Will Wait for a Data Lock in MySQL? If you issue a UPDATE or DELETE statement on a row that has an exclusive lock owned by another session, your statement will be blocked to wait for the other session to release the lock. But the wait will be timed out after the predefined inn... 2017-04-28, 1742🔥, 0💬

Experiment with Data Locks in MySQL
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Database Basics and Terminologies in MySQL
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