我們如何基於另一個檢視建立 MySQL 檢視?
在 MySQL 中,我們可以基於其他檢視建立一個檢視。要了解這一點,我們有檢視“Info”,其資料如下 -
mysql> Create view info AS Select Id, Name, Subject FROM student_info; Query OK, 0 rows affected (0.11 sec) mysql> Select * from Info; +------+---------+------------+ | Id | Name | Subject | +------+---------+------------+ | 101 | YashPal | History | | 105 | Gaurav | Literature | | 125 | Raman | Computers | | NULL | Ram | Computers | +------+---------+------------+ 4 rows in set (0.00 sec)
現在,藉助以下查詢,我們正在建立另一個檢視名稱為“info_less”,它基於現有檢視“info” -
mysql> Create view info_less AS Select Id, Name, Subject FROM info WHERE id >= 120; Query OK, 0 rows affected (0.25 sec) mysql> Select * from info_less; +------+-------+-----------+ | Id | Name | Subject | +------+-------+-----------+ | 125 | Raman | Computers | +------+-------+-----------+ 1 row in set (0.03 sec)
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