SQL 4
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SQL WHERE 瀛愬彞
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SQL WHERE 瀛愬彞
WHERE 瀛愬彞鐢ㄤ簬鎻愬彇閭ｄ簺婊¤冻鎸囧畾鏍囧噯鐨勮褰曘€?/p>
SQL WHERE 璇硶
SELECT column_name,column_name
FROM table_name
WHERE column_name operator value;
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涓嬮潰鏄€夎嚜 "Websites" 琛ㄧ殑鏁版嵁锛?/p>
+----+--------------+---------------------------+-------+---------+ | id | name | url | alexa | country | +----+--------------+---------------------------+-------+---------+ | 1 | Google | https://www.google.cm/ | 1 | USA | | 2 | 娣樺疂 | https://www.taobao.com/ | 13 | CN | | 3 | 鑿滈笩鏁欑▼ | http://www.runoob.com/ | 4689 | CN | | 4 | 寰崥 | http://weibo.com/ | 20 | CN | | 5 | Facebook | https://www.facebook.com/ | 3 | USA | +----+--------------+---------------------------+-------+---------+
WHERE 瀛愬彞瀹炰緥
涓嬮潰鐨?SQL 璇彞浠?"Websites" 琛ㄤ腑閫夊彇鍥藉涓?"CN" 鐨勬墍鏈夌綉绔欙細
SELECT * FROM Websites WHERE country=鈥楥N鈥?
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SELECT * FROM Websites WHERE id<>1;
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WHERE 瀛愬彞涓殑杩愮畻绗?/h2>
涓嬮潰鐨勮繍绠楃鍙互鍦?WHERE 瀛愬彞涓娇鐢細
| 杩愮畻绗?/th> | 鎻忚堪 |
|---|---|
| = | 绛変簬 |
| <> | 涓嶇瓑浜庛€?strong>娉ㄩ噴锛?/strong>鍦?SQL 鐨勪竴浜涚増鏈腑锛岃鎿嶄綔绗﹀彲琚啓鎴?!= |
| > | 澶т簬 |
| < | 灏忎簬 |
| >= | 澶т簬绛変簬 |
| <= | 灏忎簬绛変簬 |
| BETWEEN | 鍦ㄦ煇涓寖鍥村唴 |
| LIKE | 鎼滅储鏌愮妯″紡 |
| IN | 鎸囧畾閽堝鏌愪釜鍒楃殑澶氫釜鍙兘鍊?/td> |
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