如何在 UPDATE 查询中执行三个表 JOIN?

2021-11-20 00:00:00 join mysql

我提出了一个问题并得到了帮助.

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

如果有三个表涉及这样的事情，我现在希望这样做.

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

    UPDATE tableC c JOIN tableB b JOIN tableA a

我的问题基本上是...是否可以在 UPDATE 语句上进行三个表连接?它的正确语法是什么?

My question is basically... is it possible to do three table joins on an UPDATE statement? And what is the correct syntax for it?

我是否执行以下操作?

 JOIN tableB, tableA
 JOIN tableB JOIN tableA

推荐答案

答案是是，你可以.

试试这个:

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

对于一般更新加入:

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

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