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                [TOC] 視圖是一個虛擬表,其內容由查詢定義。同真實的表一樣,視圖包含一系列帶有名稱的列和行數據。但是,視圖并不在數據庫中以存儲的數據值集形式存在。行和列數據來自由定義視圖的查詢所引用的表,并且在引用視圖時動態生成。為什么使用視圖,某部分原因是從安全方面考慮,將部分表字段分配到視圖中,重要字段不分配,提高數據庫安全性。 ## 查看視圖 ~~~ mysql>show table status where comment="view"; ~~~ ## 創建視圖 ~~~ mysql>create view tmpstu as select username,sex,num from stu; ~~~ ## 刪除視圖 ~~~ mysql>drop view tmpstu; ~~~ ## 修改視圖 ~~~ mysql>alter view tmpstu asselect id,name,age from stu; ~~~
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