字符串处理func_split，func_split_TotalLength

举例：   将字符串：‘abc,abcd,abcde,abcdef'  以',' 分割 取出第几个字符。

CREATE  FUNCTION `func_split`(`f_string` text character set utf8 ,`f_delimiter` varchar(5),`f_order` int)
RETURNS varchar(9999)
BEGIN
DECLARE result VARCHAR(9999) character set utf8 default '';
set result=REVERSE(SUBSTRING_INDEX(REVERSE(SUBSTRING_INDEX(f_string,f_delimiter,f_order)),f_delimiter,1));
RETURN result;
END ;

select func_split('a,ab,abc,abcd,abcde,abcdef',',',3);

abc；

select func_split('a|ab|abc|abcd|abcde|abcdef','|',4);

abcd；

CREATE DEFINER = `zkf`@`localhost` FUNCTION `func_split_TotalLength`(`f_string` text character set utf8 ,`f_delimiter` varchar(5))
RETURNS int(11)
BEGIN
RETURN 1+(LENGTH(f_string)-LENGTH(replace(f_string,f_delimiter,'')));
END ;

select func_split_TotalLength('a,ab,abc,abcd,abcde,abcdef',',')；

6;

select func_split_TotalLength('a|ab|abc|abcd|abcde','|');

5;

通常嵌套再循环中使用对每个结果操作。如下：

CREATE  PROCEDURE `D_AUTHORITY`(IN `d_authority_id` varchar(20000),IN `controlParameter` varchar(8888))
BEGIN
DECLARE cnt int DEFAULT 0;
DECLARE i int DEFAULT 0;
set cnt=func_split_TotalLength(d_authority_id,',');
while i < cnt
do 
set i=i+1;
update db_role r 
set r.authority_ids = replace(r.authority_ids,CONCAT(func_split(d_authority_id,',',i),','),'');
update db_role r 
set r.authority_ids = replace(r.authority_ids,CONCAT(',',func_split(d_authority_id,',',i)),'');
update db_authority a
set a.delete_authority = '1' where a.authority_id=func_split(d_authority_id,',',i);

end WHILE;
END;