Declare Cursor dynamically - mysql

Question

I need to create Cursors dynamically in stored procedure based on what situation i'm in, the ideal is below:
IF (varOrgGroupCode = '') THEN
BEGIN
DECLARE groupCode CURSOR FOR
SELECT `groupcode` FROM `LICENSEKEYS`;
END;
ELSE
BEGIN
DECLARE groupCode CURSOR FOR
SELECT `groupcode` FROM `LICENSEKEYS` WHERE `groupcode` = varOrgGroupCode;
END;
END IF;
The code above will cause an syntax error. I've googled & someone did it by using temp table. Can anyone tell me how please?

Answer 1

Probably the thing you found on Google was to create a temp table, populate that temp table based on your predicate and then reference the temp table in your cursor declaration.
Something like this:
DELIMITER $$
CREATE PROCEDURE `some_procedure`(IN varOrgGroupCode varchar(100))
BEGIN
DECLARE bNoMoreRows BOOLEAN DEFAULT FALSE;
DECLARE vGroupCode varchar(100);
DECLARE groupCode CURSOR FOR
SELECT `groupcode` FROM `LICENSEKEYS_TEMP`;
declare continue handler for not found set bNoMoreRows := true;
BEGIN
drop table if exists LICENSEKEYS_TEMP;
create temporary table `LICENSEKEYS_TEMP` (groupCode varchar(100));
IF (varOrgGroupCode = '') THEN
insert into `LICENSEKEYS_TEMP` (groupCode) SELECT `groupcode` FROM `LICENSEKEYS`;
ELSE
insert into `LICENSEKEYS_TEMP` (groupCode) SELECT `groupcode` FROM `LICENSEKEYS` WHERE `groupcode` = varOrgGroupCode;
END IF;
open groupCode;
GROUPCODE_LOOP: loop
fetch groupCode into vGroupCode;
-- Do some stuff
if bNoMoreRows then
close groupCode;
leave GROUPCODE_LOOP;
end if;
END LOOP GROUPCODE_LOOP;
END;
END$$
DELIMITER ;