Mysql stored procedure outer cursor fails to loop - mysql

Question

Hi I have a nested cursor with three levels on it...
DECLARE campaign_csr CURSOR FOR SELECT cid FROM tempCampaign;
DECLARE date_csr CURSOR FOR SELECT header,ranges FROM tempDate ORDER BY id;
DECLARE level_csr CURSOR FOR SELECT 1st,2nd,3rd FROM tempDispoLevels ORDER BY 1st,2nd;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET v_done := TRUE;
OPEN campaign_csr;
campaign_loop:LOOP
FETCH campaign_csr INTO xcid;
IF v_done THEN
CLOSE campaign_csr;
LEAVE campaign_loop;
END IF;
select "1";
OPEN date_csr;
date_loop: LOOP
FETCH date_csr INTO xheader,xranges;
IF v_done THEN
SET v_done := FALSE;
CLOSE date_csr;
LEAVE date_loop;
END IF;
select "2";
OPEN level_csr;
level_loop: LOOP
FETCH level_csr INTO x1level,x2level,x3level;
IF v_done THEN
SET v_done := FALSE;
CLOSE level_csr;
LEAVE level_loop;
END IF;
select "3";
END LOOP level_loop;
END LOOP date_loop;
END LOOP campaign_loop;
the problem is the outer loop (which in this case campaign_loop) doesn't read all records. Is there any way around this.
Thank you.

Answer 1

You know each outer loop has not finished when you process an inner loop (otherwise you wouldn't be processing the inner loop), so simply reset v_done after each inner loop:
SET v_done := FALSE;
That's all you need to do.
Don't create a boolean variable for each cursor and copy the value; logically they can only ever be true!

Answer 2

I discover a work around on this: The added variables are for looping the outside cursor until to the last row.
Declare 3 more v_done variable
DECLARE v_done BOOLEAN DEFAULT FALSE; //this is the original
DECLARE v_done1 BOOLEAN DEFAULT FALSE; //added
DECLARE v_done2 BOOLEAN DEFAULT FALSE; //added
DECLARE v_done3 BOOLEAN DEFAULT FALSE;//added
Keep this line:
DECLARE CONTINUE HANDLER FOR NOT FOUND SET v_done := TRUE;
Change every declaration of cursor:
OPEN campaign_csr;
campaign_loop:LOOP
FETCH campaign_csr INTO xcid;
IF v_done THEN
CLOSE campaign_csr;
LEAVE campaign_loop;
END IF;
into:
OPEN campaign_csr;
campaign_loop:LOOP
FETCH campaign_csr INTO xcid;
SET v_done1 := v_done;
IF v_done1 THEN
SET v_done := FALSE;
CLOSE campaign_csr;
LEAVE campaign_loop;
END IF;
This code works for me.
DELIMITER $$
USE `yourDatabase`$$
DROP PROCEDURE IF EXISTS `yourProcedure`$$
CREATE DEFINER=`root`#`localhost` PROCEDURE `yourProcedure`()
BEGIN
DECLARE xcid INT;
DECLARE xcid2 INT;
DECLARE xcid3 INT;
DECLARE v_done BOOLEAN DEFAULT FALSE;
DECLARE v_done1 BOOLEAN DEFAULT FALSE;
DECLARE v_done2 BOOLEAN DEFAULT FALSE;
DECLARE v_done3 BOOLEAN DEFAULT FALSE;
DECLARE campaign_csr CURSOR FOR SELECT column FROM yourTable;
DECLARE date_csr CURSOR FOR SELECT column FROM yourTable2;
DECLARE level_csr CURSOR FOR SELECT column FROM yourTable3;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET v_done := TRUE;
OPEN campaign_csr;
campaign_loop:LOOP
FETCH campaign_csr INTO xcid;
SET v_done1 := v_done;
IF v_done1 THEN
SET v_done := FALSE;
CLOSE campaign_csr;
LEAVE campaign_loop;
END IF;
select "1";
OPEN date_csr;
date_loop: LOOP
FETCH date_csr INTO xcid2;
SET v_done2 := v_done;
IF v_done2 THEN
SET v_done := FALSE;
CLOSE date_csr;
LEAVE date_loop;
END IF;
select "2";
OPEN level_csr;
level_loop: LOOP
FETCH level_csr INTO xcid2;
SET v_done3 := v_done;
IF v_done3 THEN
SET v_done := FALSE;
CLOSE level_csr;
LEAVE level_loop;
END IF;
select "3";
END LOOP level_loop;
END LOOP date_loop;
END LOOP campaign_loop;
END$$
DELIMITER ;