3在UPDATE查询中如何做表JOIN? [英] How to do 3 table JOIN in UPDATE query?

问题描述

我问了一个问题，得到了答复，这很有帮助.

I asked a question and got this reply which helped.

   UPDATE TABLE_A a JOIN TABLE_B b 
   ON a.join_col = b.join_col AND a.column_a = b.column_b 
   SET a.column_c = a.column_c + 1

现在，如果有3张桌子，我正在考虑这样做 像这样的东西.

Now I am looking to do this if there are 3 tables involved something like this.

    UPDATE tableC c JOIN tableB b JOIN tableA a

我的问题基本上是...这可能在UPDATE语句上进行3个表联接吗?正确的语法是什么?谢谢你.我会做...

my question is basically... is this possible to do 3 table join on an UPDATE statement? and what is the correct syntax for it? Thank you. Do i do the...

 JOIN tableB, tableA
 JOIN tableB JOIN tableA

推荐答案

答案是yes您可以

那样尝试

UPDATE TABLE_A a 
    JOIN TABLE_B b ON a.join_col = b.join_col AND a.column_a = b.column_b 
    JOIN TABLE_C c ON [condition]
SET a.column_c = a.column_c + 1

对于常规更新，请加入:

For general Update join :

   UPDATE TABLEA a 
   JOIN TABLEB b ON a.join_colA = b.join_colB  
   SET a.columnToUpdate = [something]

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