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Today, I will talk to you about how to use update to achieve multi-table joint updates in Mysql, many people may not know much about it. In order to make you understand better, the editor has summarized the following content for you. I hope you can get something according to this article.

1. Execute UPDATE student s, class c SET s.classrooms nameplates testing 00 WHERE s.class_id = c.id

Student table class table

two。 Execute UPDATE student s JOIN class c ON s.class_id = c.id SET s.classrooms nameplate tests 11 minutes, menagerie c. Stubs nameplates tests 11'

Student table class table

3. Execute UPDATE student s LEFT JOIN class c ON s.class_id = c.id SET s.classrooms nameplate tests 22 minutes, magnets c. Stubs nameplates tests 22'

Student table class table

4. Execute UPDATE student s RIGHT JOIN class c ON s.class_id = c.id SET s.classrooms nameplate tests 33 minutes, magnets c. Stubs nameplates tests 33'

Student table class table

5. Execute UPDATE student s JOIN class c ON s.class_id = c.id SET s.class_name=c.name, c.stu_name=s.name

Student table class table

Knowledge points to add:

Mysql multi-table association update

In daily development, we usually write single-table update statements, rarely write multi-table associated update.

Unlike SQL Server, there are some small differences in the methods used between update's multi-table join update and select's multi-table join query in MySQL.

Let's look at a specific example.

Update orders o left join users u on o.userId = u.idset o.userName = u.name; after reading the above, do you have any further understanding of how to use update to achieve multi-table joint update in Mysql? If you want to know more knowledge or related content, please follow the industry information channel, thank you for your support.

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