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1-3 DROP VIEW: 刪除一個觀點

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MYSQL學習心得
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- <span style="color:#292929;"><span style="font-family:rockwell condensed;"><span style="font-size:24.0pt;">View</span></span></span><span style="color:#292929;"><span style="font-family:ms pgothic;"><span style="font-size:24.0pt;">的優點：</span></span></span>
 
<div style="margin-left:.79in;"><span style="color:#292929;"><span style="font-family:ms pgothic;"><span style="font-size:20.0pt;">可提供邏輯資料獨立性 </span></span></span><span style="color:#292929;"><span style="font-family:rockwell condensed;"><span style="font-size:20.0pt;">(Logical Data Independence)</span></span></span></div><div style="margin-left:.79in;"><span style="color:#292929;"><span style="font-family:ms pgothic;"><span style="font-size:20.0pt;">隱藏不需要或具私密性的資料</span></span></span></div><div style="margin-left:.79in;"><span style="color:#292929;"><span style="font-family:ms pgothic;"><span style="font-size:20.0pt;">同一關聯可建立多種不同的觀點，讓使用者以不同的角度看同一份資料。</span></span></span></div>- <span style="color:#292929;"><span style="font-family:rockwell condensed;"><span style="font-size:24.0pt;">View</span></span></span><span style="color:#292929;"><span style="font-family:ms pgothic;"><span style="font-size:24.0pt;">的缺點：</span></span></span>
 
<div style="margin-left:.79in;"><span style="color:#292929;"><span style="font-family:ms pgothic;"><span style="font-size:20.0pt;">觀點的更新</span></span></span><span style="color:#292929;"><span style="font-family:rockwell condensed;"><span style="font-size:20.0pt;">(Update)</span></span></span><span style="color:#292929;"><span style="font-family:ms pgothic;"><span style="font-size:20.0pt;">有諸多限制，無法與關聯提供相同的功能。</span></span></span></div><div style="margin-left:.79in;"> </div>- 參考資料:<http://www.codedata.com.tw/database/mysql-tutorial-11-views/>