mysql

DELIMITER $$

USE `ytt`$$

DROP FUNCTION IF EXISTS `func_instr_simple_ytt`$$

CREATE DEFINER=`root`@`localhost` FUNCTION `func_instr_simple_ytt`(

f_str VARCHAR(1000), -- Parameter 1

f_substr VARCHAR(100),  -- Parameter 2

f_replace_str varchar(100),

f_times int -- times counter.only support  3.

) RETURNS varchar(1000)

BEGIN

declare v_result varchar(1000) default 'ytt'; -- result.

declare v_substr_len int default 0; -- search string length.

set f_times = 3; -- only support  3.

set v_substr_len = length(f_substr);

select instr(f_str,f_substr) into @p1; -- First real position .

select instr(substr(f_str,@p1+v_substr_len),f_substr) into @p2; Secondary virtual position.

select instr(substr(f_str,@p2+ @p1 +2*v_substr_len - 1),f_