set maximum value to a column

Question

I have a table with a column (int type) called age. This column should hold maximun value 50. If it exceeds then it shouldn't update that row.

Means this column shold take values from 0 to 50.

If I try to update that to 51 then that shouldn't allow.

Could any one help....!

Answer 1

Try this:

CREATE TRIGGER check_trigger
  BEFORE INSERT
  ON table
  FOR EACH ROW
BEGIN
  IF NEW.age<0 OR NEW.age>50 THEN
    CALL `Error: Wrong values for age`; -- this trick will throw an error
  END IF;
END