Question

I am having trouble with the CASE statement in this procedure:

DELIMITER //
CREATE PROCEDURE getRowsByHourHalfday(xhour smallint)
BEGIN
     SET @twelveless = xhour - 12;
     SELECT CASE
          WHEN (xhour, > 11) THEN SET @realhour = ( xhour - 12); 
          ELSE SET @realhour = xhour; 
     END CASE;
     SET @first = @realhour * 60;
     SET @next = @first + 59;
     SELECT * FROM mydb.halfday WHERE minutepart BETWEEN @first AND @next;
END //
DELIMITER ;

This is the pseudo-code for what I am trying:

if hour > 11 then
    set newhour = hour - 12;
    set first = newhour * 60;
else 
    set first = hour * 60;
endif
select * from halfday where minutepart between first and (first + 60);

Answer 1

Instead of your SELECT CASE statement, through to END CASE, you should have the following:

   SET @realhour = CASE WHEN xhour > 11 THEN xhour - 12 ELSE xhour END CASE