MySQL Multiple table association data Delete SQL statements at the same time

Delete Deletes multiple table data, how can you delete data from multiple relational tables at the same time? Here's an in-depth explanation:

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1 delete from T1 where condition 2 delete t1 from T1 where condition 3 Delete t1 from t1,t2 where condition 4 Delete t1,t2 from t1,t2 where condition

Category (Column information table) and news (press data sheet).

The ID (column number) field in the category is used as the primary key (primary key) for the table. The only information that identifies a column.
The ID field in news is the primary key (primary key) for the table. The only information that identifies a column.

The category_id (column number) field is associated with the ID field of the category table.

1.SQL DELETE statement

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Delete category,news from category left JOIN news on category.id = news.category_id

1, from the data table t1 those ID values in the datasheet T2 have a matching record of all deleted 1

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Delete T1 from t1,t2 where t1.id=t2.id or DELETE from T1 USING t1,t2 where t1.id=t2.id

2, from the datasheet T1 in the data table T2 no matching records to find out and delete 1

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DELETE T1 from T1 left join T2 on t1.id=t2.id WHERE t2.id is NULL or DELETE from t1,using T1 left join T2 on T1.id=t2.id WH ERE T2.id is NULL

3, from the two tables to find the same record of data and two of the data in the table deleted 1

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DELETE t1,t2 from T1 left JOIN T2 on T1.id=t2.id WHERE t1.id=25

Note that the t1,t2 in the delete t1,t2 from here cannot be an alias

such as: 1

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Delete T1,T2 from table_name as T1 left join Table2_name as T2 on T1.id=t2.id where table_name.id=25

Executing in the data is wrong (MYSQL version is not less than 5.0 in 5.0 is OK)

The above statement is rewritten as 1

code is as follows	copy code
delete Table_name,table2_name from table_name as T1 left join Table2_name as T2 on t1.id=t2.id where table_name.id=25