Not able to find problwm with this small stored proc

[Ankur Srivastava]

Hi everyone.
I am using mysql 5.6 and new to programming in mysql. Can anyone help me find the problem with the following code.First two cursors work fine, but as soon as I add the third one, I get into trouble.

Please help.

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BEGIN
declare route_done boolean;
declare bus_done boolean;
declare dev_done boolean;
declare routeId int;
declare busId varchar(20);
declare timest int;
declare lat double default -1;
declare lng double default -1;
declare lnglat varchar (100) default "NA";
declare onroute boolean ;
declare startPoint int;
declare endPoint int;
declare startgeom point;
declare endgeom point;
declare currgeom point;
declare routegeom linestring;

DECLARE curRoutes CURSOR FOR select distinct assigned_route_id from bus;

DECLARE CONTINUE HANDLER FOR NOT FOUND SET route_done = TRUE;

OPEN curRoutes;
cur_route_loop: LOOP
FETCH FROM curRoutes INTO routeId;
IF route_done THEN
CLOSE curRoutes;
LEAVE cur_route_loop;
END IF;

set startgeom = (SELECT station_point FROM station WHERE id = (select from_id from route where id = routeId));
set endgeom = (SELECT station_point FROM station WHERE id = (select to_id from route where id = routeId));
set routegeom = (Select routegeomvals from route where id = routeId);
BLOCKBus: BEGIN
DECLARE curBuses CURSOR FOR SELECT bus_id FROM bus where assigned_route_id = routeId ;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET bus_done = TRUE;

OPEN curBuses;
cur_bus_loop: LOOP
FETCH FROM curBuses INTO busId;
IF bus_done THEN
set bus_done = false;
CLOSE curBuses;
LEAVE cur_bus_loop;
END IF;

BLOCKDev: BEGIN
DECLARE curDevs CURSOR FOR (select ts,latitude,longitude from ent.eventdata where accountID='rc' and deviceid = busId) ;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET dev_done = TRUE;

OPEN curDevs;
cur_dev_loop: LOOP
FETCH FROM curDevs INTO timest,lat,lng;
IF dev_done THEN
set dev_done = false;
CLOSE curDevs;
LEAVE cur_dev_loop;
END IF;

set lnglat = CONCAT(cast(lng as char),' ',cast(lat as char));
set currgeom = GeomFromText('POINT(lnglat)');

if(!(SELECT if (ST_Intersects(routegeom, Buffer(currgeom,.001))))) then
insert into tbloffroute values (busId, routeId, from_unixtime(timest));
end if;

if (select if(ST_within(startgeom, currgeom))) then
insert into tblstartend(busId,routeId,from_unixtime(timest),'s');
end if;

if (select if(ST_within(endgeom, currgeom))) then
insert into tblstartend(busId,routeId,from_unixtime(timest),'e');
end if;

END LOOP cur_dev_loop;
END BLOCKDev;




END LOOP cur_bus_loop;
END BLOCKBus;

END LOOP cur_route_loop;
END