若何咱们念建立一个视图，按照某些特定前提从表外猎取值，那末咱们必需正在建立视图时应用 WHERE 子句。与决于 WHERE 子句的值将存储正在视图外。应用 WHERE 子句建立 MySQL 视图的语法如高 -
语法
Create View view_name AS Select_statements FROM table WHERE condition(s);
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事例
为了阐明上述观念，咱们运用表“Student_info”外的下列数据 -
mysql> Select * from student_info; +------+---------+------------+------------+ | id | Name | Address | Subject | +------+---------+------------+------------+ | 101 | YashPal | Amritsar | History | | 105 | Gaurav | Chandigarh | Literature | | 1二5 | Raman | Shimla | Computers | | 130 | Ram | Jhansi | Computers | +------+---------+------------+------------+ 4 rows in set (0.08 sec)
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而今，还助下列盘问，咱们将创立视图名称“Info”，其前提是存储仅以计较机做为主题的止。因而，咱们正在创立视图时需求利用 WHERE 子句，如高所示 -
mysql> Create OR Replace VIEW Info AS Select Id, Name, Address, Subject from student_info WHERE Subject = 'Computers'; Query OK, 0 rows affected (0.46 sec) mysql> Select * from info; +------+-------+---------+-----------+ | Id | Name | Address | Subject | +------+-------+---------+-----------+ | 1两5 | Raman | Shimla | Computers | | 130 | Ram | Jhansi | Computers | +------+-------+---------+-----------+ 二 rows in set (0.00 sec)
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以上即是假如创立一个 MySQL 视图，按照某些前提从表外猎取值？的具体形式，更多请存眷萤水红IT仄台此外相闭文章！
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