Updating a table joining another table

Question

Hi,

Update a table joining 1 more table.

UPDATE t1 SET  t1.col1 =1 FROM table1 t1 JOIN  table2 t2 
ON t1.ID=t2.ID
WHERE t1.Name='Test' AND t2.Age=25;

i get this error,You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'FROM table1 t1 JOIN table2 t2 ...

Any thoughts?

Thanks.

Answer 1

There shouldn't be a FROM clause in the UPDATE statement, and the SET clause should follow the full set of table references:

UPDATE  table1 t1 
JOIN    table2 t2 ON t1.ID = t2.ID
SET     t1.col1 = 1
WHERE   t1.Name = 'Test' AND t2.Age = 25;

Test case:

CREATE TABLE table1 (id int, col1 int, name varchar(20));
CREATE TABLE table2 (id int, age int);

INSERT INTO table1 VALUES (1, 0, 'Test');
INSERT INTO table1 VALUES (2, 0, 'Test');
INSERT INTO table1 VALUES (3, 0, 'No Test');

INSERT INTO table2 VALUES (1, 20);
INSERT INTO table2 VALUES (2, 25);
INSERT INTO table2 VALUES (3, 25);

Result:

SELECT * FROM table1;
+------+------+---------+
| id   | col1 | name    |
+------+------+---------+
|    1 |    0 | Test    |
|    2 |    1 | Test    |
|    3 |    0 | No Test |
+------+------+---------+
3 rows in set (0.00 sec)