如何在 UPDATE 查询中执行3表 JOIN?

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

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

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

转载于:https://stackoverflow.com/questions/15209414/how-to-do-3-table-join-in-update-query

the answer is yes you can

try it like that

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

EDIT:

For general Update join :

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

Alternative way of achieving same result is not to use JOIN keyword at all.

UPDATE TABLE_A, TABLE_B
SET TABLE_A.column_c = TABLE_B.column_c + 1
WHERE TABLE_A.join_col = TABLE_B.join_col

An alternative General Plan, which I'm only adding as an independent Answer because the blasted "comment on an answer" won't take newlines without posting the entire edit, even though it isn't finished yet.

UPDATE table A
JOIN table B ON {join fields}
JOIN table C ON {join fields}
JOIN {as many tables as you need}
SET A.column = {expression}

Example:

UPDATE person P
JOIN address A ON P.home_address_id = A.id
JOIN city C ON A.city_id = C.id
SET P.home_zip = C.zipcode;

Below is the Update query which includes JOIN & WHERE both. Same way we can use multiple join/where clause, Hope it will help you :-

UPDATE opportunities_cstm oc JOIN opportunities o ON oc.id_c = o.id
 SET oc.forecast_stage_c = 'APX'
 WHERE o.deleted = 0
   AND o.sales_stage IN('ABC','PQR','XYZ')

For PostgreSQL example:

UPDATE TableA AS a
SET param_from_table_a=FALSE -- param FROM TableA
FROM TableB AS b
WHERE b.id=a.param_id AND a.amount <> 0;