MySQL 表一列逗号分隔字段，按逗号切割

直接查询

---切割前

select id,content from test_split;

1 12,13,14

2 21,25

3 33

--切割后

1 12

1 13

1 14

2 21

2 25

3 33

--执行sql

SELECT a.id,SUBSTRING_INDEX(SUBSTRING_INDEX(a.content,',',b.help_topic_id+1),',',-1) AS num

FROM test_split a join

mysql.help_topic b on b.help_topic_id < LENGTH(a.content)-LENGTH(REPLACE(a.content,',',''))+1;

 

 

存储过程游标入库

---切割前

select id,content from test_split;

1 12,13,14

2 21,25

3 33

--切割后

select id,content from test_split_open;

1 12

1 13

1 14

2 21

2 25

3 33

 

-------------创建表和插入测试数据

-- ----------------------------

-- Table structure for test_split

-- ----------------------------

DROP TABLE IF EXISTS `test_split`;

CREATE TABLE `test_split` (

`id` int(11) NOT NULL,

`content` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,

PRIMARY KEY (`id`) USING BTREE

) ENGINE = InnoDB CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

 

-- ----------------------------

-- Records of test_split

-- ----------------------------

INSERT INTO `test_split` VALUES (1, '12,13,14');

INSERT INTO `test_split` VALUES (2, '21,25');

INSERT INTO `test_split` VALUES (3, '33');

 

-- ----------------------------

-- Table structure for test_split_open

-- ----------------------------

DROP TABLE IF EXISTS `test_split_open`;

CREATE TABLE `test_split_open` (

`id` int(11) NOT NULL,

`content` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL

) ENGINE = InnoDB CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

 

-------------切割存储过程

CREATE PROCEDURE `p_Split`()
BEGIN
	DECLARE sid int;
	DECLARE scontent varchar(255);
	
  DECLARE s int DEFAULT 0;
	DECLARE ct CURSOR FOR select a.id,a.content from test_split a;
	DECLARE CONTINUE HANDLER FOR SQLSTATE '02000' SET s=1;
	OPEN ct; 
    FETCH ct into sid,scontent;
		while s <> 1 DO
			insert into test_split_open(`id`,`content`) SELECT 
					sid,SUBSTRING_INDEX(SUBSTRING_INDEX(scontent,',',help_topic_id+1),',',-1) AS num 
			FROM 
					mysql.help_topic 
			WHERE 
					help_topic_id < LENGTH(scontent)-LENGTH(REPLACE(scontent,',',''))+1;
		FETCH ct INTO sid,scontent;
    end WHILE;
	CLOSE ct;
END

--执行存储过程

call p_split();