MYSQL中利用select查詢某字段中包含以逗號分隔的字符串的記錄方法
首先我們建立一張帶有逗號分隔的字符串。
CREATE TABLE test(id int(6) NOT NULL AUTO_INCREMENT,PRIMARY KEY (id),pname VARCHAR(20) NOT NULL,pnum VARCHAR(50) NOT NULL);
然後插入帶有逗號分隔的測試數據
INSERT INTO test(pname,pnum) VALUES('產品1','1,2,4');
INSERT INTO test(pname,pnum) VALUES('產品2','2,4,7');
INSERT INTO test(pname,pnum) VALUES('產品3','3,4');
INSERT INTO test(pname,pnum) VALUES('產品4','1,7,8,9');
INSERT INTO test(pname,pnum) VALUES('產品5','33,4');
查找pnum字段中包含3或者9的記錄
mysql> SELECT * FROM test WHERE find_in_set('3',pnum) OR find_in_set('9',pnum);
+----+-------+---------+
| id | pname | pnum |
+----+-------+---------+
| 3 | 產品3 | 3,4 |
| 4 | 產品4 | 1,7,8,9 |
+----+-------+---------+
2 rows in set (0.03 sec)
使用正則
mysql> SELECT * FROM test WHERE pnum REGEXP '(3|9)';
+----+-------+---------+
| id | pname | pnum |
+----+-------+---------+
| 3 | 產品3 | 3,4 |
| 4 | 產品4 | 1,7,8,9 |
| 5 | 產品5 | 33,4 |
+----+-------+---------+
3 rows in set (0.02 sec)
這樣會產生多條記錄,比如33也被查找出來了,不過MYSQL還可以使用正則,挺有意思的
find_in_set()函數返回的所在的位置,如果不存在就返回0
mysql> SELECT find_in_set('e','h,e,l,l,o');
+------------------------------+
| find_in_set('e','h,e,l,l,o') |
+------------------------------+
| 2 |
+------------------------------+
1 row in set (0.00 sec)
還可以用來排序,如下;
mysql> SELECT * FROM TEST WHERE id in(4,2,3);
+----+-------+---------+
| id | pname | pnum |
+----+-------+---------+
| 2 | 產品2 | 2,4,7 |
| 3 | 產品3 | 3,4 |
| 4 | 產品4 | 1,7,8,9 |
+----+-------+---------+
3 rows in set (0.03 sec)
如果想要按照ID為4,2,3這樣排序呢?
mysql> SELECT * FROM TEST WHERE id in(4,2,3) ORDER BY find_in_set(id,'4,2,3');
+----+-------+---------+
| id | pname | pnum |
+----+-------+---------+
| 4 | 產品4 | 1,7,8,9 |
| 2 | 產品2 | 2,4,7 |
| 3 | 產品3 | 3,4 |
+----+-------+---------+
3 rows in set (0.03 sec)