This article focuses on interviews. In interviews, you only need to answer the key points. You do not need to have a very in-depth answer to the framework. If you want to cope with the interview, it is enough. Grasp the key points.
Interviewer: Has MySQL ever encountered a deadlock problem? How did you solve it?
Deadlocks can occur when multiple transactions compete for the same resources at the same time. Deadlock refers to a situation where two or more transactions are waiting for each other to release lock resources, causing all transactions to be unable to continue.
The following are the steps and operating commands to solve the MySQL deadlock problem:
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Monitor deadlocks:
Check if there is a deadlock using the following command:
SHOW ENGINE INNODB STATUS;This returns an output with detailed information, including deadlock detection information.
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To solve the deadlock:
Once a deadlock is found, you can take the following methods to solve the deadlock problem:
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Rollback transaction:
Use the following command to roll back a transaction to relieve the deadlock:
ROLLBACK; -
Kill the process:
Use the following command to find the process causing the deadlock:
SHOW PROCESSLIST;Once you find the process ID causing the deadlock, kill the process using the following command:
KILL <process_id>; -
Adjust transaction order:
Within an application, you can adjust the order of transactionsÿ
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