用navicat创建函数

DELIMITER ;;

CREATE DEFINER=`root`@`%` FUNCTION `dateformat`(

`dateTi` VARCHAR(50)

)

RETURNS varchar(30)

LANGUAGE SQL

DETERMINISTIC

CONTAINS SQL

SQL SECURITY DEFINER

COMMENT ''

BEGIN

     RETURN (SELECT case  WHEN SUBSTRING(dateTi,6,2)<=3 THEN 'Q1'  WHEN SUBSTRING(dateTi,6,2)>3 and  SUBSTRING(dateTi,6,2)<=6 THEN 'Q2' WHEN SUBSTRING(dateTi,6,2)>6 and SUBSTRING(dateTi,6,2)<=9 THEN 'Q3' ELSE 'Q4' END );

END

;;