What is the syntax of mysql left outer join query

1. Join the left table as the main table, display all the data in the main table, and query the data in the right table according to the conditions. If the condition is met, it is displayed; if not, it is null.

2. It can be understood as ensuring that all data in the left table is displayed based on internal connections.

Syntax

select 字段 from a left [outer] join b on 条件

Example

Use left join to query the class table and student table

Here As is used to alias the table in order to write a simple

select * from students as s right join classes as c on s.cls_id = c.id;

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