Question

How to make the following statement to work in MySQL?

UPDATE my_table t1 SET column_1 = 
(SELECT column_1 FROM my_table t2 WHERE t2.id = (t1.id - 1))
WHERE t1.type = 2

I am getting a "You can't specify target table 't1' for update in FROM clause" error.

Answer 1

You can update with a join:

UPDATE my_table t1
    JOIN my_table t2 ON t2.id = t1.id - 1
SET t1.column_1 = t2.column_1
WHERE t1.type = 2