mysql split函数用逗号分隔的实现

1：定义存储过程，用于分隔字符串

DELIMITER $$USE `mess`$$DROP PROCEDURE IF EXISTS `splitString`$$CREATE DEFINER=`root`@`%` PROCEDURE `splitString`(IN f_string VARCHAR(1000),IN f_delimiter VARCHAR(5))BEGIN    DECLARE cnt INT DEFAULT 0;    DECLARE i INT DEFAULT 0;    SET cnt = func_get_splitStringTotal(f_string,f_delimiter);    DROP TABLE IF EXISTS `tmp_split`;    CREATE TEMPORARY TABLE `tmp_split` (`val_` VARCHAR(128) NOT NULL) DEFAULT CHARSET=utf8;    WHILE i < cnt    DO      SET i = i + 1;      INSERT INTO tmp_split(`val_`) VALUES (func_splitString(f_string,f_delimiter,i));    END WHILE;  END$$DELIMITER ;

REPLACE(str,from_str,to_str)Returns the string str with all occurrences of the string from_str replaced by the string to_str. REPLACE() performs a case-sensitive match when searching for from_str.例如：mysql> SELECT REPLACE('www.mysql.com', 'w', 'Ww');    -> 'WwWwWw.mysql.com'

DELIMITER $$USE `mess`$$DROP FUNCTION IF EXISTS `func_get_splitStringTotal`$$CREATE DEFINER=`root`@`%` FUNCTION `func_get_splitStringTotal`(  f_string VARCHAR(10000),f_delimiter VARCHAR(50)  ) RETURNS INT(11)BEGIN   RETURN 1+(LENGTH(f_string) - LENGTH(REPLACE(f_string,f_delimiter,'')));  END$$DELIMITER ;

（1）REVERSE(str)Returns the string str with the order of the characters reversed.例如：mysql> SELECT REVERSE('abc');    -> 'cba'（2）SUBSTRING_INDEX(str,delim,count)Returns the substring from string str before count occurrences of the delimiter delim. If count is positive, everything to the left of the final delimiter (counting from the left) is returned. If count is negative, everything to the right of the final delimiter (counting from the right) is returned. SUBSTRING_INDEX() performs a case-sensitive match when searching for delim.例如：mysql> SELECT SUBSTRING_INDEX('www.mysql.com', '.', 2);    -> 'www.mysql'mysql> SELECT SUBSTRING_INDEX('www.mysql.com', '.', -2);    -> 'mysql.com'

DELIMITER $$USE `mess`$$DROP FUNCTION IF EXISTS `func_splitString`$$CREATE DEFINER=`root`@`%` FUNCTION `func_splitString`( f_string VARCHAR(1000),f_delimiter VARCHAR(5),f_order INT) RETURNS VARCHAR(255) CHARSET utf8BEGIN    DECLARE result VARCHAR(255) DEFAULT '';    SET result = REVERSE(SUBSTRING_INDEX(REVERSE(SUBSTRING_INDEX(f_string,f_delimiter,f_order)),f_delimiter,1));    RETURN result;  END$$DELIMITER ;

（1）调用存储过程：

CALL splitString('1,3,5,7,9',',');

（2）：查看临时表

SELECT val_ FROM tmp_split AS t1;

结果：

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