1、具体函数:
# 函数:func_split_TotalLength
DELIMITER $$
DROP function IF EXISTS `func_split_TotalLength` $$
CREATE DEFINER=`root`@`%` FUNCTION `func_split_TotalLength`
(f_string varchar (1000),f_delimiter varchar (5)) RETURNS int (11)
BEGIN
# 计算传入字符串的总length
return 1+(length(f_string) - length( replace (f_string,f_delimiter, '' )));
END $$
DELIMITER;
# 函数:func_split
DELIMITER $$
DROP function IF EXISTS `func_split` $$
CREATE DEFINER=`root`@`%` FUNCTION `func_split`
(f_string varchar (1000),f_delimiter varchar (5),f_order int ) RETURNS varchar (255) CHARSET utf8
BEGIN
# 拆分传入的字符串,返回拆分后的新字符串
declare result varchar (255) default '' ;
set result = reverse(substring_index(reverse(substring_index(f_string,f_delimiter,f_order)),f_delimiter,1));
return result;
END $$
DELIMITER;
# 存储过程:splitString
DELIMITER $$
DROP PROCEDURE IF EXISTS `splitString` $$
CREATE PROCEDURE `splitString`
( IN f_string varchar (1000), IN f_delimiter varchar (5))
BEGIN
# 拆分结果
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` (`status` varchar (128) not null ) DEFAULT CHARSET=utf8;
while i < cnt
do
set i = i + 1;
insert into tmp_split(`status`) values (func_split(f_string,f_delimiter,i));
end while;
END $$
DELIMITER;
2、测试是否能成功分割
call splitString( "apple,banana,orange,pears,grape" , "," );
select * from tmp_split;
运行结果如下,说明分割成功:
mysql> call splitString( "apple,banana,orange,pears,grape" , "," );
select * from tmp_split;
Query OK, 1 row affected
+ --------+ | status | +--------+ | apple | | banana | | orange | | pears | | grape | +--------+ 5 rows in set
mysql>
3、应用 where in ()查询
# 先传入字符串,分割后保存在临时表tmp_split中
call splitString( "apple,banana,orange,pears,grape" , "," );
# 将查询的结果作为其他查询的条件来使用
select * from fruit where in ( select * from tmp_split);
以上就是利用MySQL存储过程分割字符串的方法介绍。
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