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This article is about how mysql sets the isolation level of things. The editor thought it was very practical, so I shared it with you as a reference. Let's follow the editor and have a look.

Mysql sets the isolation level of transactions: execute the [set session transaction isolation level read uncommitted] command, which means to set the read uncommitted level.

Isolation level

The isolation levels of transactions are divided into uncommitted reads (read uncommitted), committed reads (read committed), repeatable reads (repeatable read), and serialization (serializable).

Unsubmitted read

A transaction was executed but not committed; B transaction queried the updated data of A transaction; A transaction rolled back;-dirty data appeared

Submitted for reading

A transaction performs updates; B transactions query; A transactions perform updates; when B transactions query again, the data are inconsistent;-cannot be read repeatedly

Repeatable read

No matter how many times A transaction is executed, as long as it is not committed, the query value of B transaction remains the same; B transaction only queries the data snapshot at the beginning of B transaction.

Serialization

Concurrent read and write operations are not allowed. When writing is executed, the read must wait.

Specific commands:

/ / set mysql isolation level: set session transaction isolation level transaction isolation level / / set read uncommitted level: set session transaction isolation level read uncommitted;// set read committed level: set session transaction isolation level read committed;// set repeatable read level: set session transaction isolation level repeatable read;// set serializable level: set session transaction isolation level serializable; thank you for reading! The method of setting the isolation level of things in mysql is shared here. I hope the above content can be of some help to you, so that you can learn more knowledge. If you think the article is good, you can share it and let more people see it.

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