mysql 通配符%以及_

%匹配任意长度

_ 匹配单个字符

mysql> select * from table1;
+----------+------------+-----+---------------------+-------+
| name_new | transactor | pid | order_date          | price |
+----------+------------+-----+---------------------+-------+
| 1hahha   | 1xiaohong  |    | -- :: |      |
| 2hahha   | 2xiaohong  |    | -- :: |      |
| 3hahha   | 3xiaohong  |    | -- :: |      |
| 4hahha   | 4xiaohong  |    | -- :: |      |
| 3hahha   | bob        |    | -- :: |      |
| 3hahha   | lee        |    | -- :: |      |
| 3hahha   | lee        |    | -- :: |      |
| 3hahha   | lee        |    | -- :: |      |
| 3hahha   | bob        |    | -- :: |      |
| 3hahha   | bob        |   | -- :: |      |
+----------+------------+-----+---------------------+-------+
 rows in set (0.00 sec)

mysql> select * from table1 where transactor like "%xiaohong";
+----------+------------+-----+---------------------+-------+
| name_new | transactor | pid | order_date          | price |
+----------+------------+-----+---------------------+-------+
| 1hahha   | 1xiaohong  |    | -- :: |      |
| 2hahha   | 2xiaohong  |    | -- :: |      |
| 3hahha   | 3xiaohong  |    | -- :: |      |
| 4hahha   | 4xiaohong  |    | -- :: |      |
+----------+------------+-----+---------------------+-------+
 rows in set (0.00 sec)

mysql> select * from table1 where transactor like "xiaohong";
Empty set (0.00 sec)

mysql> select * from table1 where transactor like "%xiao";
Empty set (0.00 sec)

mysql> select * from table1 where transactor like "%xiao%";
+----------+------------+-----+---------------------+-------+
| name_new | transactor | pid | order_date          | price |
+----------+------------+-----+---------------------+-------+
| 1hahha   | 1xiaohong  |    | -- :: |      |
| 2hahha   | 2xiaohong  |    | -- :: |      |
| 3hahha   | 3xiaohong  |    | -- :: |      |
| 4hahha   | 4xiaohong  |    | -- :: |      |
+----------+------------+-----+---------------------+-------+
 rows in set (0.00 sec)

mysql> select * from table1 where transactor like "_xiao%";
+----------+------------+-----+---------------------+-------+
| name_new | transactor | pid | order_date          | price |
+----------+------------+-----+---------------------+-------+
| 1hahha   | 1xiaohong  |    | -- :: |      |
| 2hahha   | 2xiaohong  |    | -- :: |      |
| 3hahha   | 3xiaohong  |    | -- :: |      |
| 4hahha   | 4xiaohong  |    | -- :: |      |
+----------+------------+-----+---------------------+-------+
 rows in set (0.00 sec)