mysql if使用实例

//DELIMITER
DROP PROCEDURE if EXISTS createAmountCount;
create PROCEDURE createAmountCount()
BEGIN
DECLARE ss VARCHAR(20);
DECLARE sqt VARCHAR(200);
set ss=‘test‘;
set sqt=‘select * from test WHERE 1=1 AND NAME<>‘‘‘‘ {0}  ‘;
select if(ss is null,sqt,CONCAT(sqt,‘and date>= ‘));
END;
//DELIMITER
CALL createAmountCount();