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
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Change Transaction Isolation Level in MySQL
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Transaction Waiting for a Data Lock in MySQL
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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, 3324🔥, 0💬

Experiment with Data Locks in MySQL
How To Experiment Data Locks in MySQL? If you want to have some experience with data locks, you can create two windows running two mysql transactions in two sessions. In session 1, you can run a UPDATE statement with REPEATABLE READ transaction isolation level to create an exclusive lock. Before com... 2017-04-28, 3242🔥, 0💬

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