如何通过从基表中选择基于模式匹配的数据来创建 MySQL 视图?

mysqlmysqli database

MySQL LIKE 运算符用于根据模式匹配选择数据。同样,我们可以将 LIKE 运算符与视图结合使用,以从基表中选择基于模式匹配的特定数据。为了理解这个概念,我们使用具有以下数据的基表"student_info" −

mysql> Select * from Student_info;
+------+---------+------------+------------+
| id   | Name    | Address    | Subject    |
+------+---------+------------+------------+
| 101  | YashPal | Amritsar   | History    |
| 105  | Gaurav  | Chandigarh | Literature |
| 125  | Raman   | Shimla     | Computers  |
| 130  | Ram     | Jhansi     | Computers  |
| 132  | Shyam   | Chandigarh | Economics  |
| 133  | Mohan   | Delhi      | Computers  |
+------+---------+------------+------------+
6 rows in set (0.00 sec)

示例

以下查询将创建一个名为‘Info’的视图,使用‘LIKE’运算符根据模式匹配选择一些特定值 −

mysql> Create or Replace view Info AS SELECT * from student_info WHERE Name LIKE '%Ra%';
Query OK, 0 rows affected (0.11 sec)

mysql> Select * from Info;
+------+--------+------------+------------+
| id   | Name   | Address    | Subject    |
+------+--------+------------+------------+
| 105  | Gaurav | Chandigarh | Literature |
| 125  | Raman  | Shimla     | Computers  |
| 130  | Ram    | Jhansi     |  Computers |
+------+--------+------------+------------+
3 rows in set (0.00 sec)

我们也可以将 NOT 与 LIKE 运算符一起使用,如下所示 −

mysql> Create or Replace view Info AS SELECT * from student_info WHERE Name NOT LIKE'%Ra%';
Query OK, 0 rows affected (0.14 sec)

mysql> Select * from info;
+------+---------+------------+-----------+
| id   | Name    | Address    | Subject   |
+------+---------+------------+-----------+
| 101  | YashPal | Amritsar   | History   |
| 132  | Shyam   | Chandigarh | Economics |
| 133  | Mohan   | Delhi      | Computers |
+------+---------+------------+-----------+
3 rows in set (0.00 sec)

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