mysql函数split功能实现

先设置：set global log_bin_trust_function_creators = 1;

1. 函数func_splitstringtotal：将字符串按指定方式分割，并计算单元总数

delimiter $$
create function `func_get_splitstringtotal`(
f_string varchar(10000),f_delimiter varchar(50)
) returns int(11)
begin
return 1+(length(f_string) - length(replace(f_string,f_delimiter,'')));
end$$
delimiter ;

2.函数func_splitstring：将字符串按指定方式分割，获取指定位置的数

delimiter $$
drop function if exists `func_splitstring` $$
create function `func_splitstring`
( f_string varchar(1000),f_delimiter varchar(5),f_order int)
returns varchar(255) charset utf8
begin

declare result varchar(255) default '';
set result = reverse(substring_index(reverse(substring_index(f_string,f_delimiter,f_order)),f_delimiter,1));
return result;
end$$
select func_splitstring('1,2,3,4,5,6,7',',',1);

3.过程splitstring 将字符串分割，并放到临时表tmp_split 里面

delimiter $$
drop procedure if exists `splitstring` $$
create procedure `splitstring`
(in f_string varchar(1000),in f_delimiter varchar(5))

begin
declare cnt int default 0;
declare i int default 0;
set cnt = func_split_totallength(f_string,f_delimiter);
drop table if exists `tmp_split`;
create temporary table `tmp_split` (`val_` varchar(128) not null) default charset=utf8;

while i < cnt
do
set i = i + 1;
insert into tmp_split(`val_`) values (func_split(f_string,f_delimiter,i));
end while;
end$$
call splitstring('a,s,d,f,g,h,j',',');
select * from tmp_split;