pro-select-limit-if

drop procedure if exists p9;
CREATE PROCEDURE p9 ()
BEGIN
DECLARE a INT;
DECLARE b INT;
DECLARE c INT;
SET a = 5;
SET b = 5;
SET c = IF(b>0,b,18446744073709551615); 

SELECT c;

SELECT * FROM traceroleid LIMIT a,c;
#SELECT * FROM traceroleid LIMIT 0,IF(@tm>0,@tm,1111);
#SELECT * FROM investorinfo LIMIT a,b;

END;