Question

I know this won’t work. I tried it in various forms and failed all times. What is the simplest way to achieve the following result?

ALTER TABLE XYZ AUTO_INCREMENT = (select max(ID) from ABC);

This is great for automation projects.

SELECT @max := (max(ID)+1) from ABC;        -> This works!
select ID from ABC where ID = (@max-1);     -> This works!
ALTER TABLE XYZ AUTO_INCREMENT = (@max+1);  -> This fails :( Why?

Answer 1

Use a prepared statement:

  SELECT @max := MAX(ID)+ 1 FROM ABC;

  PREPARE stmt FROM 'ALTER TABLE ABC AUTO_INCREMENT = ?';
  EXECUTE stmt USING @max;

  DEALLOCATE PREPARE stmt;