{"id":5771,"date":"2024-04-15T16:57:55","date_gmt":"2024-04-15T08:57:55","guid":{"rendered":"http:\/\/zyg.luchers.cn\/?p=5771"},"modified":"2024-04-15T16:57:55","modified_gmt":"2024-04-15T08:57:55","slug":"%e7%ac%ac%e4%ba%8c%e7%ab%a0%e3%80%81%e5%85%b3%e7%b3%bb%e6%95%b0%e6%8d%ae%e5%ba%93","status":"publish","type":"post","link":"http:\/\/zyg.luchers.cn\/index.php\/2024\/04\/15\/%e7%ac%ac%e4%ba%8c%e7%ab%a0%e3%80%81%e5%85%b3%e7%b3%bb%e6%95%b0%e6%8d%ae%e5%ba%93\/","title":{"rendered":"\u7b2c\u4e8c\u7ae0\u3001\u5173\u7cfb\u6570\u636e\u5e93"},"content":{"rendered":"

\u7b2c\u4e8c\u7ae0\u3001\u5173\u7cfb\u6570\u636e\u5e93<\/h1>\n

\u5173\u7cfb\u6570\u636e\u5e93\u7b80\u4ecb<\/p>\n

\"image-20230816210359709\"<\/div><\/p>\n

2.1\u3001\u5173\u7cfb\u6570\u636e\u7ed3\u6784\u53ca\u5f62\u5f0f\u5316\u5b9a\u4e49<\/h2>\n

2.1.1\u3001\u5173\u7cfb<\/h3>\n

1\u3001\u5355\u4e00\u7684\u6570\u636e\u7ed3\u6784\u2014\u2014\u5173\u7cfb<\/p>\n

2\u3001\u903b\u8f91\u7ed3\u6784\u2014\u2014\u4e8c\u7ef4\u8868<\/p>\n

3\u3001\u5173\u7cfb\u6a21\u578b\u662f\u5efa\u7acb\u5728\u96c6\u5408\u4ee3\u6570\u7684\u57fa\u7840\u4e0a<\/p>\n

1\u3001\u76f8\u5173\u5b9a\u4e49<\/h4>\n

1\u3001\u57df\uff08Domain\uff09<\/h5>\n

1\u3001\u5c5e\u6027\u7684\u53d6\u503c\u8303\u56f4<\/p>\n

2\u3001\u5c31\u662f\u5217<\/p>\n

2\u3001\u7b1b\u5361\u5c14\u79ef\uff08Cartesain Product\uff09<\/h5>\n

1\u3001\u5b9a\u4e49 <\/p>\n

\"image-20230816211653671\"<\/div><\/p>\n
3\u3001\u5143\u7ec4\uff08Tuple\uff09<\/h5>\n

1\u3001\u5c31\u662f\u4e8c\u7ef4\u8868\u4e2d\u7684\u4e00\u884c<\/p>\n

4\u3001\u5206\u91cf\uff08Compoent\uff09<\/h5>\n

1\u3001\u7b1b\u5361\u5c14\u79ef\u5143\u7d20\uff08d1\uff0cd2\uff0c\u2026\u2026\uff0cdn)\u4e2d\u7684di\u4e2a\u79f0\u4e3a\u5206\u91cf<\/p>\n

5\u3001\u57fa\u6570\uff08Cardinal number\uff09<\/h5>\n

1\u3001\u4ecb\u7ecd<\/p>\n

\"image-20230816212201227\"<\/div><\/p>\n

2\u3001\u5c31\u662f\u53d6\u503c\u8303\u56f4\u80fd\u53d6\u51e0\u4e2a\u6570<\/p>\n

6\u3001\u7b1b\u5361\u5c14\u79ef\u7684\u8868\u793a\u65b9\u6cd5<\/h5>\n

1\u3001\u7b1b\u5361\u5c14\u79ef\u53ef\u4ee5\u8868\u793a\u4e3a\u4e00\u4e2a\u4e8c\u7ef4\u6570\u7ec4\u8868<\/p>\n

2\u3001\u8868\u4e2d\u6bcf\u4e00\u884c\u5bf9\u5e94\u4e00\u4e2a\u5143\u7ec4<\/p>\n

3\u3001\u6bcf\u4e00\u5217\u5bf9\u5e94\u4e00\u4e2a\u57df<\/p>\n

4\u3001\u4f8b\u5b50<\/p>\n

\"image-20230816213316706\"<\/div><\/p>\n

2\u3001\u5173\u7cfb\uff08Relational\uff09<\/h4>\n

1\u3001\u5173\u7cfb<\/h5>\n

1\u3001R\uff08D1\uff0cD2\u2026\u2026\uff0cDn\uff09<\/p>\n

2\u3001\u5176\u4e2dR\u8868\u793a\u5173\u7cfb\u540d<\/p>\n

3\u3001n\u8868\u793a\u5173\u7cfb\u7684\u76ee\u6570\uff0c\u5c31\u662f\u4e2a\u6570<\/p>\n

2\u3001\u5143\u7ec4<\/h5>\n

1\u3001\u6bcf\u4e2a\u5143\u7d20\u662f\u5173\u7cfb\u4e2d\u7684\u5143\u7ec4\uff0c\u901a\u5e38\u7528t\u8868\u793a<\/p>\n

3\u3001\u5355\u5143\u5173\u7cfb\u4e0e\u4e8c\u5143\u5173\u7cfb<\/h5>\n

1\u3001n=1\u65f6\uff1a\u5355\u5143\u5173\u7cfb<\/p>\n

2\u3001n-2\u65f6\uff1a\u4e8c\u5143\u5173\u7cfb<\/p>\n

4\u3001\u5173\u7cfb\u7684\u8868\u793a<\/h5>\n

1\u3001\u5173\u7cfb\u662f\u4e00\u4e2a\u4e8c\u7ef4\u8868<\/p>\n

2\u3001\u6bcf\u884c\u5bf9\u5e94\u4e00\u4e2a\u5143\u7ec4<\/p>\n

3\u3001\u6bcf\u5217\u5bf9\u5e94\u4e00\u4e2a\u57df<\/p>\n

4\u3001\u4e00\u4e2a\u5c5e\u6027<\/p>\n

5\u3001\u5c5e\u6027<\/h5>\n

1\u3001\u4e3a\u4e86\u533a\u522b\u76f8\u540c\u7684\u57df\uff0c\u6240\u4ee5\u5217\u5bf9\u5e94\u7684\u540d\u5b57\u5c31\u53eb\u5c5e\u6027<\/p>\n

2\u3001n\u6709\u51e0\u4e2a\uff0c\u5c5e\u6027\u5c31\u6709\u51e0\u4e2a<\/p>\n

6\u3001\u7801<\/h5>\n

1\u3001\u5019\u9009\u7801\uff08Candidate key\uff09\uff1a\u552f\u4e00\u5730\u6807\u8bc6\u4e00\u4e2a\u5143\u7ec4\uff0c\u7b80\u5355\u60c5\u51b5\uff1a\u5019\u9009\u7801\u53ea\u5305\u542b\u4e00\u4e2a\u5c5e\u6027<\/p>\n

2\u3001\u5168\u7801\uff08All-key\uff09\uff1a\u6781\u7aef\u60c5\u51b5\uff1a\u5173\u7cfb\u6a21\u5f0f\u7684\u6240\u6709\u5c5e\u6027\u7ec4\u79f0\u4e3a\u4e00\u4e2a\u5173\u7cfb\u6a21\u5f0f\u7684\u5019\u9009\u7801<\/p>\n

3\u3001\u4e3b\u7801\uff1a\u82e5\u6709\u591a\u4e2a\u5019\u9009\u7801\uff0c\u5219\u9009\u5b9a\u5176\u4e2d\u4e00\u4e2a\u4e3a\u4e3b\u7801\uff08Primary key\uff09<\/p>\n

4\u3001\u4e3b\u5c5e\u6027\uff1a\u5019\u9009\u7801\u7684\u8bf8\u5c5e\u6027\u79f0\u4e3a\u4e3b\u5c5e\u6027<\/p>\n

5\u3001\u975e\u4e3b\u5c5e\u6027\uff1a\u4e0d\u5305\u542b\u5728\u4efb\u4f55\u5019\u9009\u7801\u4e2d\u7684\u5c5e\u6027\u3001\u6216\u975e\u7801\u5c5e\u6027<\/p>\n

6\u3001\u4f8b\u5b50<\/h5>\n

1\u3001\u7b1b\u5361\u5c14\u79ef\u7684\u5b50\u96c6\u5e76\u4e0d\u662f\u90fd\u6709\u5b9e\u9645\u610f\u4e49<\/p>\n

2\u3001\u4f8b\u5b50<\/p>\n

\"image-20230816215203482\"<\/div><\/p>\n
7\u3001\u4e09\u7c7b\u5173\u7cfb<\/h5>\n

1\u3001\u57fa\u672c\u5173\u7cfb\uff1a\u5b9e\u9645\u5b58\u5728\u7684\u8868\uff0c\u662f\u5b9e\u9645\u5b58\u50a8\u6570\u636e\u7684\u903b\u8f91\u8868\u793a<\/p>\n

2\u3001\u67e5\u8be2\u8868\uff1a\u67e5\u8be2\u7ed3\u679c\u5bf9\u5e94\u7684\u8868<\/p>\n

3\u3001\u89c6\u56fe\u8868\uff1a\u7531\u57fa\u672c\u8868\u6216\u5176\u4ed6\u89c6\u56fe\u8868\u5bfc\u51fa\u7684\u8868\uff0c\u662f\u865a\u8868\uff0c\u4e0d\u5bf9\u5e94\u5b9e\u9645\u5b58\u50a8\u7684\u6570\u636e<\/p>\n

8\u3001\u57fa\u672c\u5173\u7cfb\u7684\u6027\u8d28<\/h5>\n

1\u3001\u5217\u662f\u540c\u8d28\u7684\uff08Homogeneous\uff09<\/p>\n

2\u3001\u4e0d\u540c\u7684\u5217\u53ef\u80fd\u51fa\u81ea\u540c\u4e00\u4e2a\u57df\uff0c\u5176\u4e2d\u7684\u6bcf\u4e00\u4e2a\u5217\u79f0\u4e00\u4e2a\u5c5e\u6027\uff0c\u4e0d\u540c\u7684\u5c5e\u6027\u8981\u57fa\u4e8e\u4e0d\u540c\u7684\u5c5e\u6027\u540d\uff0c\uff08\u4f8b\u5982\uff1a\u5b66\u751f\u548c\u6027\u522b\u4e0d\u662f\u540c\u4e00\u5217\uff0c\u4f46\u90fd\u662f\u6c49\u5b57\u7c7b\u578b\u7684\u8fd9\u4e2a\u57df\uff09<\/p>\n

3\u3001\u5217\u7684\u987a\u5e8f\u662f\u65e0\u6240\u8c13\uff0c\u5217\u7684\u6b21\u5e8f\u53ef\u4ee5\u4ea4\u6362<\/p>\n

4\u3001\u4efb\u610f\u4e24\u4e2a\u5143\u7ec4\u7684\u5019\u9009\u7801\u4e0d\u80fd\u76f8\u540c\uff08\u4f8b\u5982\u4e24\u4e2a\u8eab\u4efd\u8bc1\u53f7\u4e0d\u80fd\u76f8\u540c\uff09<\/p>\n

5\u3001\u884c\u7684\u987a\u5e8f\u65e0\u6240\u8c13\uff0c\u884c\u7684\u6b21\u5e8f\u53ef\u4ee5\u4ea4\u6362<\/p>\n

6\u3001\u5206\u91cf\u5fc5\u987b\u53d6\u539f\u5b50\u503c\uff0c\u89c4\u8303\u6761\u4ef6\u4e2d\u6700\u57fa\u672c\u7684\u4e00\u6761<\/p>\n

2.1.2\u3001\u5173\u7cfb\u6a21\u5f0f<\/h3>\n

1\u3001\u4ec0\u4e48\u662f\u5173\u7cfb\u6a21\u5f0f<\/h4>\n

1\u3001\u662f\u5bf9\u5173\u7cfb\u7684\u63cf\u8ff0\uff08\u5173\u7cfb\u6a21\u578b\u5c31\u50cf\u6a21\u5177\uff09<\/p>\n

1\u3001\u5143\u7ec4\u96c6\u5408\u7684\u7ed3\u6784<\/h5>\n

1\u3001\u5c5e\u6027\u7ed3\u6784\u3001\u5c5e\u6027\u6765\u81ea\u57df\u3001\u5c5e\u6027\u4e0e\u57df\u4e4b\u95f4\u7684\u6620\u8c61\u5173\u7cfb<\/p>\n

2\u3001\u4e00\u4e2a\u5173\u7cfb\u901a\u5e38\u7531\u8d4b\u4e88\u5b83\u7684\u5143\u7ec4\u8bed\u4e49\u786e\u5b9a<\/h5>\n
3\u3001\u73b0\u5b9e\u7684\u4e16\u754c\u4e2d\u8fd8\u5b58\u5728\u7684\u5b8c\u6574\u6027\u7ea6\u675f<\/h5>\n

2\u3001\u5b9a\u4e49\u5173\u7cfb\u6a21\u5f0f<\/h4>\n

1\u3001\u5185\u5bb9<\/p>\n

\"image-20230816221212332\"<\/div><\/p>\n

3\u3001\u5173\u7cfb\u6a21\u5f0f\u4e0e\u5173\u7cfb<\/h4>\n

1\u3001\u5173\u7cfb\u6a21\u5f0f\u662f\u9759\u6001\u7684\u7a33\u5b9a\u7684\uff08\u7c7b\u4f3c\u8868\u5934\uff09<\/p>\n

2\u3001\u5173\u7cfb\u662f\u52a8\u6001\u7684\u3001\u968f\u65f6\u95f4\u4e0d\u65ad\u53d8\u5316\uff08\u7c7b\u4f3c\u8868\u4e2d\u6570\u636e\uff09<\/p>\n

3\u3001\u6839\u636e\u67d0\u4e00\u65f6\u523b\u7684\u72b6\u6001\u6216\u5185\u5bb9\uff0c\u5728\u5b9e\u9645\u5f00\u53d1\u4e2d\u5f00\u53d1\u95ee\u95ee\u79f0\u4e3a\u5173\u7cfb\uff0c\u9700\u8981\u4e0a\u4e0b\u6587\u52a0\u4ee5\u8fa8\u522b<\/p>\n

2.1.3\u3001\u5173\u7cfb\u6570\u636e\u5e93<\/h3>\n

1\u3001\u5173\u7cfb\u6570\u636e\u5e93<\/h4>\n

1\u3001\u7ed9\u5b9a\u7684\u5e94\u7528\u9886\u57df\u4e2d\uff0c\u6240\u6709\u5173\u7cfb\u7684\u96c6\u5408\u6784\u6210\u7684\u5173\u7cfb\u6570\u636e\u5e93<\/p>\n

2\u3001\u5173\u7cfb\u6570\u636e\u5e93\u7684\u578b\u4e0e\u503c<\/h4>\n

1\u3001\u5173\u7cfb\u6570\u636e\u5e93\u7684\u578b<\/h5>\n

1\u3001\u5173\u7cfb\u6570\u636e\u5e93\u6a21\u5f0f\u3001\u5bf9\u5173\u7cfb\u6570\u636e\u5e93\u7684\u63cf\u8ff0<\/p>\n

2\u3001\u5173\u7cfb\u6570\u636e\u5e93\u7684\u6a21\u5f0f<\/h5>\n

1\u3001\u82e5\u5e72\u57df\u7684\u5b9a\u4e49\uff0c\u5728\u8fd9\u4e9b\u57df\u4e0a\u5b9a\u4e49\u7684\u4e00\u4e2a\u82e5\u5e72\u5173\u7cfb\u6a21\u5f0f<\/p>\n

3\u3001\u5173\u7cfb\u6570\u636e\u5e93\u7684\u503c<\/h5>\n

1\u3001\u5173\u7cfb\u6a21\u5f0f\u5728\u67d0\u4e00\u523b\u5bf9\u5e94\u7684\u5173\u7cfb\u7684\u96c6\u5408\uff0c\u7b80\u79f0\u5173\u7cfb\u6570\u636e\u5e93<\/p>\n

2.1.4\u3001\u5173\u7cfb\u6a21\u578b\u7684\u5b58\u50a8\u7ed3\u6784<\/h3>\n

1\u3001\u6709\u7684\u5173\u7cfb\u6570\u636e\u5e93\u7ba1\u7406\u7cfb\u7edf\u4e2d\uff1a\u4e00\u4e2a\u8868\u5bf9\u5e94\u4e00\u4e2a\u64cd\u4f5c\u7cfb\u7edf\u6587\u4ef6\uff0c\u5c06\u7269\u7406\u6570\u636e<\/p>\n

2\u3001\u6709\u7684\u5173\u7cfb\u6570\u636e\u5e93\u7ba1\u7406\u7cfb\u7edf\u4ece\u64cd\u4f5c\u7cfb\u7edf\u90a3\u91cc\u7533\u8bf7\u82e5\u5e72\u4e2a\u5927\u6587\u4ef6\uff0c\u81ea\u5df1\u5212\u5206\u6587\u4ef6\u7a7a\u95f4\uff0c\u7ec4\u7ec7\u8868\uff0c\u7d22\u5f15\u7b49\u5b58\u50a8\u7ed3\u6784\uff0c\u5e76\u8fdb\u884c\u5b58\u50a8\u7ba1\u7406 <\/p>\n

2.2\u3001\u5173\u7cfb\u6570\u636e\u7ed3\u6784<\/h2>\n

2.2.1\u3001\u57fa\u672c\u5173\u7cfb\u64cd\u4f5c<\/h3>\n

1\u3001\u5e38\u7528\u7684\u5173\u7cfb\u64cd\u4f5c<\/h4>\n

1\u3001\u67e5\u8be2\uff1a\u9009\u62e9\u3001\u6295\u5f71\u3001\u8fde\u63a5\u3001\u9664\u3001\u5e76\u3001\u4ea4\u3001\u5dee\u7b49<\/p>\n

\u27572\u3001\u5176\u4e2d\u9009\u62e9\u3001\u6295\u5f71\u3001\u5e76\u3001\u5dee\u3001\u7b1b\u5361\u5c14\u79ef5\u79cd\u57fa\u672c\u64cd\u4f5c<\/strong><\/p>\n

3\u3001\u6570\u636e\u66f4\u65b0\uff1a\u63d2\u5165\u3001\u4fee\u6539\u3001\u5220\u9664<\/p>\n

4\u3001\u67e5\u8be2\u7684\u8868\u8fbe\u80fd\u529b\u662f\u5176\u4e2d\u6700\u4e3b\u8981\u7684\u90e8\u5206<\/p>\n

2\u3001\u5173\u7cfb\u64cd\u4f5c\u7684\u7279\u70b9<\/h4>\n

1\u3001\u96c6\u5408\u64cd\u4f5c\u65b9\u5f0f\uff1a\u64cd\u4f5c\u7684\u5bf9\u8c61\u548c\u7ed3\u679c\u90fd\u662f\u96c6\u5408\uff0c\u4e00\u6b21\u96c6\u5408\u4e00\u6b21\u65b9\u5f0f<\/p>\n

2.2.2\u3001\u5173\u7cfb\u6570\u636e\u5e93\u8bed\u8a00\u7684\u5206\u7c7b<\/h3>\n

1\u3001\u5173\u7cfb\u4ee3\u6570\u8bed\u8a00<\/h4>\n

1\u3001\u5bf9\u5173\u7cfb\u7684\u8fd0\u7b97\u6765\u8868\u8fbe\u67e5\u8be2\u8981\u6c42\u3002\u4ee3\u8868ISBL<\/p>\n

2\u3001\u5173\u7cfb\u6f14\u7b97\u8bed\u8a00<\/h4>\n

1\u3001\u7528\u8c13\u8bcd\uff08\u4f8b\u5982\u771f\u5047\uff09\u6765\u8868\u8fbe\u67e5\u8be2\u8981\u6c42<\/p>\n

2\u3001\u5143\u7ec4\u5173\u7cfb\u6f14\u7b97\u8bed\u8a00\uff1a\u8c13\u8bcd\u53d8\u5143\u7684\u57fa\u672c\u5bf9\u8c61\u662f\u5143\u7ec4\uff0c\u4ee3\u8868\uff1aAPLHA\u3001QUEL<\/p>\n

3\u3001\u57df\u5173\u7cfb\u6f14\u7b97\u8bed\u8a00\uff1a\u8c13\u8bcd\u53d8\u5143\u7684\u57fa\u672c\u5bf9\u8c61\u662f\u57df\u53d8\u91cf\uff0c\u4ee3\u8868QBF<\/p>\n

3\u3001\u5177\u6709\u5173\u7cfb\u4ee3\u6570\u548c\u5173\u7cfb\u6f14\u7b97\u53cc\u91cd\u7279\u70b9\u7684\u8bed\u8a00<\/h4>\n

1\u3001\u4ee3\u8868\uff1aSQL\uff08Structured Query Language\uff09<\/p>\n

2.3\u3001\u5173\u7cfb\u7684\u5b8c\u6574\u6027<\/h2>\n

1\u3001\u5173\u7cfb\u6a21\u578b\u4e2d\u6709\u4e09\u4e2a\u5b8c\u6574\u6027\u7ea6\u675f\uff1a\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u3001\u7528\u6237\u5b9a\u4e49\u7684\u5b8c\u6574\u6027<\/strong><\/p>\n

2\u3001\u5176\u4e2d\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u662f\u5173\u7cfb\u6a21\u578b\u5fc5\u987b\u6ee1\u8db3\u7684\u5b8c\u6574\u6027\u7ea6\u675f\u6761\u4ef6\uff0c\u79f0\u4e3a\u5173\u7cfb\u7684\u4e24\u4e2a\u4e0d\u53d8\u6027<\/strong><\/p>\n

3\u3001\u7528\u6237\u5b9a\u4e49\u7684\u5b8c\u6574\u6027\u662f\u5e94\u7528\u9886\u57df\u9700\u8981\u9075\u5faa\u7684\u7ea6\u675f\u6761\u4ef6\uff0c\u4f53\u73b0\u4e86\u5177\u4f53\u9886\u57df\u4e2d\u7684\u8bed\u4e49\u7ea6\u675f<\/p>\n

2.3.1\u3001\u5b9e\u4f53\u5b8c\u6574\u6027<\/h3>\n

1\u3001\u5b9e\u4f53\u5b8c\u6574\u6027\u89c4\u5219\uff1a\u662f\u6307\u82e5\u5c5e\u6027A\u662f\u57fa\u672c\u5173\u7cfbR\u7684\u4e3b\u5c5e\u6027\uff0c\u5219A\u4e0d\u80fd\u53d6\u7a7a\u548c\u76f8\u540c\uff08\u4f8b\u5982\uff1aA\u4e3a\u7236\u7c7b\uff0cR\u4e3a\u5b50\u7c7b\uff0c A\u4e0d\u80fd\u4e3a\u7a7a\uff09<\/p>\n

1\u3001\u5b9e\u4f53\u5b8c\u6574\u6027\u89c4\u5219\u7684\u8bf4\u660e<\/h4>\n

1\u3001\u662f\u9488\u5bf9\u57fa\u672c\u5173\u7cfb\u800c\u8a00\uff0c\u4e00\u4e2a\u57fa\u672c\u8868\u901a\u5e38\u5bf9\u5e94\u73b0\u5b9e\u4e16\u754c\u7684\u4e00\u4e2a\u5b9e\u4f53\u96c6<\/p>\n

2\u3001\u73b0\u5b9e\u4e16\u754c\u4e2d\u7684\u5b9e\u4f53\u662f\u53ef\u533a\u5206\u7684\uff0c\u5373\u5b83\u4eec\u5177\u6709\u67d0\u79cd\u552f\u4e00\u6027\u7684\u8868\u793a<\/p>\n

3\u3001\u5173\u7cfb\u6a21\u578b\u4e2d\u4ee5\u4e3b\u7801\u4f5c\u4e3a\u552f\u4e00\u6027\u6807\u8bc6<\/p>\n

4\u3001\u4e3b\u7801\u4e2d\u7684\u5c5e\u6027\u5373\u4e3b\u5c5e\u6027\u4e0d\u80fd\u53d6\u7a7a\u503c<\/p>\n

2.3.2\u3001\u53c2\u7167\u5b8c\u6574\u6027<\/h3>\n

1\u3001\u5173\u7cfb\u95f4\u7684\u5f15\u7528<\/h4>\n

1\u3001\u5728\u5173\u7cfb\u6a21\u578b\u4e2d\u5b9e\u4f53\u53ca\u5b9e\u4f53\u95f4\u90fd\u662f\u7528\u5173\u7cfb\u63cf\u8ff0\u7684\uff0c\u5b58\u5728\u7740\u5173\u7cfb\u4e0e\u5173\u7cfb\u95f4\u7684\u5f15\u7528<\/p>\n

2\u3001\u5916\u7801\uff08Foreign Key\uff09<\/h4>\n

1\u3001 \u5185\u5bb9<\/p>\n

\"image-20230816230855587\"<\/div><\/p>\n

2\u3001\u4f8b\u5b50<\/p>\n

\"image-20230816230955102\"<\/div><\/p>\n

\u89e3\u91ca\uff1aS2\u4e2d\u7684\u4e13\u4e1a\u53f7\u662f\u4e3b\u7801\uff0cS1\u4e13\u4e1a\u53f7\u4e0d\u662f\u4e3b\u7801\uff0cS1\u548cS2\u8fde\u63a5\u9760\u4e13\u4e1a\u53f7\uff0c\u6240\u4ee5S1 \u4e2d\u7684\u4e13\u4e1a\u53f7\u662f\u5916\u7801<\/p>\n

3\u3001\u4f8b\u5b50<\/p>\n

\"image-20230816231307798\"<\/div><\/p>\n

3\u3001\u8bf4\u660e<\/h4>\n

1\u3001\u5173\u7cfbR\u548cS\u4e0d\u4e00\u5b9a\u662f\u4e0d\u540c\u7684\u5173\u7cfb<\/p>\n

2\u3001\u76ee\u6807\u5173\u7cfbS\u7684\u4e3b\u7801Ks\u548c\u53c2\u7167\u5173\u7cfb\u7684\u5916\u7801F\u5fc5\u987b\u5b9a\u4e49\u5728\u540c\u4e00\u4e2a\uff08\u6216\u4e00\u7ec4\uff09\u57df\u4e0a<\/p>\n

3\u3001\u5916\u7801\u4e0d\u4e00\u5b9a\u8981\u4e0e\u4e4b\u76f8\u5bf9\u5e94\u7684\u4e3b\u7801\u540c\u540d<\/p>\n

4\u3001\u5f53\u5916\u7801\u4e0e\u54cd\u5e94\u7684\u4e3b\u7801\u5c5e\u4e8e\u4e0d\u540c\u5173\u7cfb\u65f6\uff0c\u5f80\u5f80\u53d6\u76f8\u540c\u7684\u540d\u5b57\uff0c\u4fbf\u4e8e\u8bc6\u522b<\/p>\n

4\u3001\u53c2\u7167\u5b8c\u6574\u6027\u89c4\u5219<\/h4>\n

1\u3001\u5185\u5bb9<\/p>\n

\"image-20230816231924945\"<\/div><\/p>\n

2.3.3\u3001\u7528\u6237\u5b9a\u4e49\u7684\u5b8c\u6574\u6027<\/h3>\n

1\u3001\u5185\u5bb9<\/h4>\n

1\u3001\u9488\u5bf9\u67d0\u4e00\u5177\u4f53\u5173\u7cfb\u6570\u636e\u5e93\u7684\u7ea6\u675f\u6761\u4ef6\uff0c\u53cd\u6620\u67d0\u4e00\u5177\u4f53\u5e94\u7528\u6240\u8bbe\u8ba1\u7684\u6570\u636e\u5fc5\u987b\u6ee1\u8db3\u7684\u8bed\u4e49\u8981\u6c42<\/p>\n

2\u3001\u5173\u7cfb\u6a21\u578b\u5e94\u63d0\u4f9b\u5b9a\u4e49\u548c\u68c0\u9a8c\u8fd9\u7c7b\u5b8c\u6574\u6027\u7684\u673a\u5236\uff0c\u4ee5\u4fbf\u7528\u540c\u4e00\u7684\u7cfb\u7edf\u7684\u65b9\u6cd5\u5904\u7406\uff0c\u800c\u4e0d\u8981\u6709\u7a0b\u5e8f\u627f\u5f53\u8fd9\u4e00\u529f\u80fd<\/p>\n

2.4\u3001\u5173\u7cfb\u4ee3\u6570<\/h2>\n

2.4.1\u3001\u4ecb\u7ecd<\/h4>\n

1\u3001\u5173\u7cfb\u4ee3\u6570\u662f\u4e00\u79cd\u62bd\u8c61\u7684\u67e5\u8be2\u8bed\u53e5\uff0c\u662f\u5bf9\u5173\u7cfb\uff08\u8868\uff09\u7684\u8fd0\u7b97\u6765\u8868\u8fbe\u67e5\u8be2<\/p>\n

2\u3001\u5173\u7cfb\u4ee3\u6570\u7684\u8fd0\u7b97\u5bf9\u8c61\u662f\u5173\u7cfb\uff0c\u8fd0\u7b97\u7ed3\u679c\u9875\u662f\u5173\u7cfb<\/p>\n

3\u3001\u6309\u8fd0\u7b97\u7b26\u53ef\u5206\u4e3a\u4f20\u7edf\u7684\u96c6\u5408\u8fd0\u7b97\u3001\u4e13\u95e8\u7684\u5173\u7cfb\u8fd0\u7b97<\/strong><\/p>\n

4\u3001\u96c6\u5408\u8fd0\u7b97\uff1a\u4ece\u5173\u7cfb\u7684\u6c34\u5e73\u65b9\u5411\uff0c\u5373\u884c\u7684\u89d2\u5ea6\u8fdb\u884c<\/p>\n

5\u3001\u4e13\u95e8\u7684\u5173\u7cfb\u8fd0\u7b97\uff1a\u6d89\u53ca\u884c\u548c\u5217<\/p>\n

6\u3001\u5185\u5bb9<\/p>\n

2.4.2\u3001\u4f20\u7edf\u7684\u96c6\u5408\u8fd0\u7b97<\/h4>\n
1\u3001\u5e76\uff08Union\uff09<\/h5>\n

1\u3001 \u5173\u7cfbR\u548cS\u6709\u76f8\u540c\u7684n\uff08n\u4e2a\u5c5e\u6027\uff09\uff0c\u5c5e\u6027\u90fd\u6765\u81ea\u540c\u4e00\u4e2a\u57df<\/p>\n

2\u3001R\u4e0eS\u7684\u5e76\u8fd0\u7b97\u8868\u793a\uff1aRUS<\/p>\n

3\u3001\u7ed3\u679c\uff1an\u76ee\u5173\u7cfb\uff0c\u7531\u5c5e\u4e8eR\u6216\u5c5e\u4e8eS\u7684\u5143\u7ec4\u7ec4\u6210\uff08\u628a\u4e0d\u76f8\u540c\u7684\u653e\u5728\u4e00\u8d77\uff0c\u76f8\u540c\u7684\u53ea\u7559\u4e00\u4e2a\uff09<\/p>\n

4\u3001

\"image-20230818170212389\"<\/div><\/p>\n
2\u3001\u5dee\uff08except\uff09<\/h5>\n

1\u30011\u3001 \u5173\u7cfbR\u548cS\u6709\u76f8\u540c\u7684n\uff08n\u4e2a\u5c5e\u6027\uff09\uff0c\u5c5e\u6027\u90fd\u6765\u81ea\u540c\u4e00\u4e2a\u57df<\/p>\n

2\u3001R\u4e0eS\u7684\u539f\u9178\u8868\u793a\uff1aR-S<\/p>\n

3\u3001\u8fd0\u7b97\u7ed3\u679c\uff1an\u76ee\u5173\u7cfb\uff0c\u7531\u5c5e\u4e8eR\u800c\u4e0d\u5c5e\u4e8eS\u7684\u6240\u6709\u5143\u7ec4\u7ec4\u6210<\/p>\n

4\u3001\u4f8b\u5b50<\/p>\n

\"image-20230818170221284\"<\/div><\/p>\n
3\u3001\u4ea4\uff08intersection\uff09<\/h5>\n

1\u3001\u5173\u7cfbR\u548cS\u6709\u76f8\u540c\u7684n\uff08n\u4e2a\u5c5e\u6027\uff09\uff0c\u5c5e\u6027\u90fd\u6765\u81ea\u540c\u4e00\u4e2a\u57df<\/p>\n

2\u3001R\u4e0eS\u7684\u4ea4\u8fd0\u7b97\u8868\u793a\uff1aR \u2229 S<\/p>\n

3\u3001\u8fd0\u7b97\u7ed3\u679c\uff1an\u76ee\u5173\u7cfb\uff0c\u65e2\u5c5e\u4e8eR\u53c8\u5c5e\u4e8eS\u7684\u5143\u7ec4\u7ec4\u6210<\/p>\n

4\u3001\u7b1b\u5361\u5c14\u79ef\uff08Cartesian Product\uff09<\/h5>\n

1\u3001\u662f\u5e7f\u4e49\u7684\u7b1b\u5361\u5c14\u79ef<\/p>\n

2\u3001R\uff1an\u76ee\u7684\u5173\u7cfb\uff08\u5217\uff09\uff0ck1\u4e2a\u5143\u7ec4\uff08\u884c\uff09<\/p>\n

3\u3001S\uff1am\u76ee\u5173\u7cfb\uff08\u5217\uff09\uff0ck2\u4e2a\u5143\u7ec4<\/p>\n

4\u3001R\u4e0eS\u7684\u7b1b\u5361\u5c14\u79ef\u8fd0\u7b97\u8868\u793a\uff1aR X S<\/p>\n

5\u3001\u8fd0\u7b97\u7ed3\u679c\uff1a\u884c\uff1ak1*k2\u4e2a\u5143\u7ec4\uff1b\u5217\uff1a(m+n)\u5217 \u5143\u7ec4\u7684\u96c6\u5408<\/p>\n

6\u3001\u5176\u4e2d\u5143\u7ec4\u7684\u524dn\u5217\u662f\u5173\u7cfbR\u7684\u4e00\u4e2a\u5143\u7ec4\uff0c\u540em\u5217\u662f\u5173\u7cfbS\u7684\u4e00\u4e2a\u5143\u7ec4<\/p>\n

7\u3001\u4f8b\u5b50<\/p>\n

\"image-20230818171703118\"<\/div><\/p>\n

2.4.3\u3001\u4e13\u95e8\u7684\u5173\u7cfb\u8fd0\u7b97<\/h3>\n

1\u3001\u5185\u5bb9<\/h4>\n

1\u3001\u5173\u7cfb\u8fd0\u7b97\u5305\u62ec<\/h5>\n

1\u3001\u9009\u62e9\u3001\u6295\u5f71\u3001\u8fde\u63a5\u4ef6\u3001\u9664\u8fd0\u7b97<\/p>\n

2\u3001\u76f8\u5173\u6807\u8bb0\u8bf4\u660e<\/h5>\n

1\u3001\u5185\u5bb9<\/p>\n

\"image-20230818172612818\"<\/div><\/p>\n

2\u3001\u4f8b\u5b50<\/p>\n

\"image-20230818172845822\"<\/div><\/p>\n
3\u3001\u9009\u62e9\uff08Selection\uff09<\/h5>\n

1\u3001\u5185\u5bb9<\/p>\n

\"image-20230818192817295\"<\/div><\/p>\n

2\u3001\u6761\u4ef6\u8868\u8fbe\u5f0f\u4e2d\u7684\u8fd0\u7b97\u7b26<\/p>\n

\"image-20230818192834405\"<\/div><\/p>\n

3\u3001\u4f8b\u5b50<\/p>\n

\"image-20230818193122297\"<\/div><\/p>\n
2\u3001\u6295\u5f71\uff08Projection\uff09<\/h5>\n

1\u3001\u4eceR\u4e2d\u9009\u62e9\u82e5\u5e72\u5c5e\u6027\u5217\u7ec4\u6210\u65b0\u7684\u5173\u7cfb<\/p>\n

2\u3001\u516c\u5f0f\u8868\u8fbe\u89e3\u91ca<\/p>\n

\"image-20230818193504023\"<\/div><\/p>\n

3\u3001\u4f8b\u5b50<\/p>\n

\"image-20230818193636048\"<\/div><\/p>\n
3\u3001\u8fde\u63a5\uff08Join\uff09<\/h5>\n

1\u3001\u53c8\u79f0\u4e3a\u03b8\u8fde\u63a5\uff0c\u8868\u793a\u4ece\u4e24\u4e2a\u5173\u7cfb\u7b1b\u5361\u5c14\u79ef\u4e2d\u9009\u53d6\u5c5e\u6027\u95f4\u6ee1\u8db3\u4e00\u5b9a\u6761\u4ef6\u7684\u5143\u7ec4<\/p>\n

2\u3001\u516c\u5f0f<\/p>\n

\"image-20230818194046459\"<\/div><\/p>\n

3\u3001\u8fd0\u7b97\u7ed3\u679c\uff1a\u4eceR\u548cS\u7684\u5e7f\u4e49\u7b1b\u5361\u5c14\u79efR*S\u4e2d\u9009\u53d6\uff08R\u5173\u7cfb\uff09\u5728A\u5c5e\u6027\u7ec4\u4e0a\u7684\u503c\u4e0e\uff08S\u5173\u7cfb\uff09\u5728B\u5c5e\u6027\u7ec4\u4e0a\u503c\u6ee1\u8db3\u6bd4\u8f83\u5173\u7cfb\u03b8\u7684\u5143\u7ec4<\/p>\n

2\u3001\u4e24\u7c7b\u5e38\u7528\u8fde\u63a5<\/h4>\n

1\u3001\u7b49\u503c\u8fde\u63a5<\/h5>\n

1\u3001\u03b8\u4e3a\u201c=\u201d\u7684\u8fde\u63a5\u8fd0\u7b97\u79f0\u4e3a\u7b49\u503c\u8fde\u63a5<\/p>\n

2\u3001\u7b49\u503c\u8fde\u63a5\u7684\u542b\u4e49\uff1a\u4ece\u5173\u7cfbR\u4e0eS\u7684\u5e7f\u4e49\u7b1b\u5361\u5c14\u79ef\u4e2d\u9009\u53d6A\u3001B\u5c5e\u6027\u503c\u76f8\u7b49\u7684\u90a3\u4e9b\u5143\u7ec4<\/p>\n

2\u3001\u81ea\u7136\u8fde\u63a5<\/h5>\n

1\u3001\u662f\u7279\u6b8a\u7684\u7b49\u503c\u8fde\u63a5\uff0c\u4e24\u4e2a\u8fde\u63a5\u4e2d\u8fdb\u884c\u6bd4\u8f83\u7684\u5206\u91cf\u5fc5\u987b\u662f\u76f8\u540c\u5c5e\u6027\u7ec4\uff0c\u5728\u7ed3\u679c\u4e2d\u91cd\u590d\u7684\u5c5e\u6027\u5217\u53bb\u6389<\/p>\n

2\u3001\u542b\u4e49\uff1aR\u4e0eS\u5177\u6709\u76f8\u540c\u7684\u5c5e\u6027\u7ec4B<\/p>\n

3\u3001\u6ce8\u610f\uff1a\u81ea\u7136\u8fde\u63a5\u8fd8\u9700\u8981\u53d6\u6d88\u91cd\u590d\u5217\uff0c\u6240\u4ee5\u662f\u540c\u65f6\u548c\u884c\u548c\u5217\u7684\u89d2\u5ea6\u8fdb\u884c\u8fd0\u7b97<\/p>\n

3\u3001\u4f8b\u5b50<\/h5>\n

1\u3001\u4f8b\u5b501<\/p>\n

\"image-20230818200216155\"<\/div><\/p>\n
4\u3001\u60ac\u6d6e\u5143\u7ec4<\/h5>\n

1\u3001\u4e24\u4e2a\u5173\u7cfbR\u4e0eS\u5728\u81ea\u7136\u8fde\u63a5\u65f6\uff0c\u5173\u7cfbR\u4e0eS\u4e2d\u88ab\u820d\u5f03\u7684\u5143\u7ec4\u79f0\u4e3a\u60ac\u6d6e\u5143\u7ec4<\/p>\n

5\u3001\u5916\u8fde\u63a5<\/h5>\n

1\u3001\u5982\u679c\u628a\u60ac\u6d6e\u5143\u7ec4\u820d\u5f03\u7684\u5143\u7ec4\u4e5f\u4fdd\u5b58\u5728\u7ed3\u679c\u5173\u7cfb\u4e2d\uff0c\u5728\u5176\u4ed6\u5c5e\u6027\u4e0a\u586b\u7a7a\u503c\uff08Null\uff09\uff0c\u8fd9\u79cd\u8fde\u63a5\u5c31\u53eb\u505a\u5916\u8fde\u63a5\uff08OUTER JOIN\uff09<\/p>\n

6\u3001\u5de6\u5916\u8fde\u63a5<\/h5>\n

1\u3001\u5982\u679c\u53ea\u4fdd\u7559\u5de6\u5916\u5173\u7cfbR\u4e2d\u7684\u60ac\u6d6e\u5143\u7ec4\u53eb\u505a\u5de6\u5916\u8fde\u63a5<\/p>\n

7\u3001\u53f3\u5916\u8fde\u63a5<\/h5>\n

1\u3001\u5982\u679c\u53ea\u4fdd\u7559\u53f3\u8fb9\u5173\u7cfbS\u4e2d\u7684\u60ac\u6d6e\u5143\u7ec4\u53eb\u505a\u6709\u5916\u8fde\u63a5<\/p>\n

2\u3001\u4f8b\u5b50<\/p>\n

\"image-20230818202030623\"<\/div><\/p>\n

3\u3001\u9664\u8fd0\u7b97<\/h4>\n

1\u3001\u5185\u5bb9<\/h5>\n

1\u3001\u5173\u7cfbR(X,y\uff09\u548cS(Y,Z)\uff0c\u5176\u4e2dX\uff0cY\uff0cZ\u4e3a\u5c5e\u6027\u7ec4\uff0cR\u4e2d\u7684Y\u4e0eS\u4e2d\u7684Y\u53ef\u4ee5\u6709\u4e0d\u540c\u7684\u5c5e\u6027\u540d\uff0c\u4f46\u5fc5\u987b\u51fa\u81ea\u76f8\u540c\u7684\u57df<\/p>\n

2\u3001R\u4e0eS\u7684\u9664\u8fd0\u7b97\u5f97\u5230\u4e00\u4e2a\u65b0\u7684\u5173\u7cfbP\uff08X)\uff0cP\u662fR\u4e2d\u6ee1\u8db3\u4e0b\u5217\u6761\u4ef6\u7684\u5143\u7ec4\u5728X\u5c5e\u6027\u5217\u4e0a\u7684\u6295\u5f71<\/p>\n

3\u3001\u683c\u5f0f <\/p>\n

\"image-20230822201201234\"<\/div><\/p>\n
2\u3001\u4f8b\u5b50<\/h5>\n

\"image-20230822201848605\"<\/div><\/p>\n

1\u3001\u5148\u627e\u51faR\u4e0eS\u4e2d\u4e0d\u540c\u7684A\uff0c\u627e\u5230\u6240\u6709A\u7684\u8c61\u96c6\uff0c\u518d\u5c06A\u7684\u8c61\u96c6\u548cS\u4e2d\u4e0eR\u76f8\u540c\u57df\u7684\u5143\u7d20\u5bf9\u6bd4\uff0c\u5982\u679c\u8c61\u96c6\u5305\u542b\u6240\u6709\u7684\u5143\u7d20\uff0c\u5c31\u662f\u9664\u7684\u7ed3\u679c<\/p>\n

2\u3001\u4f8b\u5b50<\/p>\n

\"image-20230822202649724\"<\/div><\/p>\n

2.5\u3001\u5173\u7cfb\u6f14\u7b97<\/h2>\n

1\u3001\u662f\u4ee5\u6570\u7406\u903b\u8f91\u4e2d\u7684\u8c13\u8bcd\u6f14\u7b97\u4e3a\u57fa\u7840\uff0c\u6309\u8c13\u8bcd\u53d8\u5143\u7684\u4e0d\u540c\uff0c\u5173\u7cfb\u6f14\u7b97\u53ef\u4ee5\u5206\u4e3a\u5143\u7ec4\u5173\u7cfb\u6f14\u7b97\u548c\u57df\u5173\u7cfb\u6f14\u7b97<\/p>\n

2.5.1\u3001\u5143\u7ec4\u5173\u7cfb\u6f14\u7b97\u8bed\u8a00ALPHA<\/h3>\n

1\u3001\u5143\u7ec4\u5173\u7cfb\u6f14\u7b97\u4ee5\u5143\u7ec4\u53d8\u91cf\u4e3a\u8c13\u8bcd\u53d8\u5143\u7684\u57fa\u672c\u5bf9\u8c61\uff0c\u4e00\u79cd\u5178\u578b\u7684\u5143\u7ec4\u5173\u7cfb\u6f14\u7b97\u8bed\u8a00\u662fALPHA<\/p>\n

2\u3001ALPHA\u8bed\u8a00\u4e3b\u8981\u6709\uff1a<\/p>\n

GET\/PUT\/HOLD\/UPDATE\/DELETE\/DROP<\/code><\/pre>\n
1\u3001\u8bed\u53e5\u7684\u57fa\u672c\u683c\u5f0f<\/h4>\n
1\u3001\u683c\u5f0f\uff1a\u64cd\u4f5c\u8bed\u53e5  \u5de5\u4f5c\u7a7a\u95f4\u540d\uff08\u8868\u8fbe\u5f0f\uff09\uff1a\u64cd\u4f5c\u6761\u4ef6<\/p>\n
2\u3001\u8868\u8fbe\u5f0f\uff1a\u7528\u4e8e\u8bf4\u660e\u67e5\u8be2\u7684\u7ed3\u679c\uff0c\u53ef\u4ee5\u662f\u5173\u7cfb\u540d\u6216\uff08\u548c\uff09\u5c5e\u6027\u540d<\/p>\n
3\u3001\u64cd\u4f5c\u6761\u4ef6\uff1a\u4e00\u4e2a\u903b\u8f91\u8868\u8fbe\u5f0f\uff0c\u8bf4\u660e\u67e5\u8be2\u7ed3\u679c\u8981\u6ee1\u8db3\u7684\u6761\u4ef6\uff0c\u7528\u4e8e\u5c06\u64cd\u4f5c\u7ed3\u679c\u9650\u5b9a\u5728\u6ee1\u8db3\u6761\u4ef6\u7684\u5143\u7ec4\u4e2d<\/p>\n
4\u3001\u8fd8\u53ef\u4ee5\u52a0\u4e0a\u6392\u5e8f\u8981\u6c42<\/p>\n
2\u3001\u68c0\u7d22\u64cd\u4f5c\uff08\u67e5\u8be2\uff09<\/h4>\n
1\u3001\u7528GET\u8bed\u53e5<\/p>\n
1\u3001\u7b80\u5355\u68c0\u7d22<\/h5>\n
1\u3001\u4e0d\u5e26\u6761\u4ef6\u7684\u68c0\u7d22<\/p>\n
2\u3001\u4f8b\u5b50<\/p>\n
\"image-20230822204834172\"<\/div><\/p>\n
2\u3001\u9650\u5b9a\u7684\u68c0\u7d22<\/h5>\n
1\u3001\u5e26\u6761\u4ef6<\/p>\n
3\u3001\u5e26\u6392\u5e8f\u7684\u68c0\u7d22<\/h5>\n
1\u3001\u5e26\u6761\u4ef6\uff0c\u8fd8\u6709\u6392\u5e8f\u529f\u80fd<\/p>\n
2\u3001DOWN\u8868\u793a\u964d\u5e8f<\/p>\n
3\u3001UP\u8868\u793a\u5347\u5e8f<\/p>\n
4\u3001\u4f8b\u5b50<\/p>\n
\"image-20230822210753608\"<\/div><\/p>\n
4\u3001\u6307\u5b9a\u8fd4\u56de\u5143\u7ec4\u7684\u4e2a\u6570<\/h5>\n
1\u3001\u5c31\u662f\u6307\u5b9a\u8fd4\u56de\u51e0\u884c<\/p>\n
2\u3001\u4f8b\u5b50<\/p>\n
\"image-20230822211148005\"<\/div><\/p>\n
5\u3001\u7528\u5143\u7ec4\u53d8\u91cf\u7684\u68c0\u7d22<\/h5>\n
1\u3001\u5c31\u662f\u7ed9\u5143\u7ec4\uff08\u884c\uff09\u53d6\u4e2a\u540d\uff08sql\u4e2d\u7528AS\uff09<\/p>\n
2\u3001\u4f5c\u7528\uff1a\u53ef\u4ee5\u7b80\u5316\u5173\u7cfb\u540d<\/p>\n
3\u3001\u64cd\u4f5c\u6761\u4ef6\u4e2d\u4f7f\u7528\u91cf\u8bcd\u65f6\u5fc5\u987b\u7528\u5143\u7ec4\u53d8\u91cf\uff0cALPHA\u8bed\u8a00\u7528RANGE\u6765\u8bf4\u5143\u7ec4\u53d8\u91cf<\/p>\n
4\u3001\u4f8b\u5b50<\/p>\n
\"image-20230822212202124\"<\/div><\/p>\n
6\u3001\u7528\u5b58\u5728\u91cf\u8bcd(existential quantifier)\u7684\u68c0\u7d22\u6761\u4ef6\u4e2d\u4f7f\u7528\u91cf\u8bcd\u65f6\u5fc5\u987b\u7528\u5143\u7ec4\u53d8\u91cf<\/h5>\n
1\u3001\u5b58\u5728\u91cf\u8bcd<\/p>\n
1\u3001\u4f8b\u5b50<\/p>\n
\"image-20230822213447814\"<\/div><\/p>\n
2\u3001\u4f8b\u5b50<\/p>\n
\"image-20230822215538394\"<\/div><\/p>\n
7\u3001\u5e26\u591a\u4e2a\u5173\u7cfb\u7684\u8868\u8fbe\u5f0f\u68c0\u7d22<\/h5>\n
1\u3001\u628a\u9898\u76ee\u4e2d\u6240\u9700\u8981\u7684\u5173\u7cfb\u5c5e\u6027\u7ed9\u8fde\u63a5\u8d77\u6765\uff08\u8868\u4e0e\u8868\u8fde\u63a5\u8d77\u6765\uff09\uff0c\u518d\u8fdb\u884c\u5224\u5b9a\u5173\u7cfb<\/p>\n
2\u3001\u4f8b\u5b50<\/p>\n
\"image-20230822221039689\"<\/div><\/p>\n
8\u3001\u7528\u5168\u79f0\u91cf\u8bcd\uff08generality quantifier\uff09\u7684\u68c0\u7d22<\/h5>\n
1\u3001\u4f8b\u5b50<\/p>\n
\"image-20230822221510351\"<\/div><\/p>\n
9\u3001\u7528\u4e24\u79cd\u91cf\u8bcd\u7684\u68c0\u7d22<\/h5>\n
1\u3001\u4f8b\u5b50<\/p>\n
\"image-20230822221544327\"<\/div><\/p>\n
10\u3001\u8574\u542b<\/h5>\n
1\u3001\u6839\u636e\u7406\u8bbaP\u2014>\u63a8\u51faq\uff0c\u5145\u5206\u6761\u4ef6<\/p>\n
2\u3001\u4f8b\u5b50\uff1ap\uff1a\u6211\u6765\u8fc7\u5317\u4eac\uff0cq\uff1a\u6211\u6765\u8fc7\u4e2d\u56fd<\/p>\n
3\u3001\u4f8b\u5b50<\/p>\n
\"image-20230822222709063\"<\/div><\/p>\n
11\u3001\u805a\u96c6\u51fd\u6570<\/h5>\n
1\u3001\u8fdb\u884c\u7b80\u5355\u8ba1\u7b97\uff0c\u5173\u7cfb\u6570\u636e\u5e93\u5efa\u7acb\u4e86\u8fd0\u7b97\u7684\u51fd\u6570\u5e93\uff0c\u901a\u5e38\u53eb\u5185\u7f6e\u51fd\u6570\uff0c\u805a\u96c6\u51fd\u6570<\/p>\n
2\u3001\u5305\u62ec:COUNT\/TOTAL\/MAX\/MIN\/AVG<\/p>\n
3\u3001\u529f\u80fd<\/p>\n
\"image-20230822222945626\"<\/div><\/p>\n
3\u3001\u66f4\u65b0\u64cd\u4f5c<\/h4>\n
1\u3001\u4fee\u6539\u64cd\u4f5c<\/h5>\n
1\u3001\u4f7f\u7528UPDATE\u8bed\u53e5<\/p>\n
2\u3001\u6b65\u9aa4\uff1a<\/p>\n
\u2460\u9996\u5148\u7528HOLD\u8bed\u53e5\u5c06\u4fee\u6539\u7684\u5143\u7ec4\u4ece\u6570\u636e\u5e93\u8bfb\u5165\u5de5\u4f5c\u7a7a\u95f4\uff08HOLD\u6709\u52a0\u9501\u529f\u80fd\uff09\n\n\u2461\u7528\u5bbf\u4e3b\u8bed\u53e5\u4fee\u6539\u5de5\u4f5c\u7a7a\u95f4\u4e2d\u5143\u7ec4\u7684\u5c5e\u6027\u503c\n\n\u2462\u6700\u540e\u7528Update\u8bed\u53e5\u5c06\u4fee\u6539\u540e\u7684\u5143\u7ec4\u9001\u56de\u6570\u636e\u5e93<\/code><\/pre>\n
3\u3001\u6ce8\u610f\uff1aUPDATE\u8bed\u53e5\uff0c\u4e00\u5b9a\u8981yonHOLD\u8bed\u53e5\u9501\u5b9a\uff0c\u907f\u514d\u5176\u4ed6\u7ba1\u7406\u5458\u4fee\u6539\u4ea7\u751f\u9519\u8bef<\/p>\n
2\u3001\u4fee\u6539\u64cd\u4f5c\u8bf4\u660e<\/h5>\n
1\u3001\u5982\u679c\u4fee\u6539\u4e24\u4e2a\u4ee5\u4e0a\u5173\u7cfb\uff08\u8868\uff09\uff0c\u5c31\u8981\u6267\u884c\u4e24\u6b21HOLD-MOVE-UPDATE\u64cd\u4f5c\u5e8f\u5217<\/p>\n
2\u3001\u5728ALPHA\u8bed\u8a00\u4e2d\uff0c\u4fee\u6539\u5173\u7cfb\u7684\u4e3b\u7801\u4e0d\u5141\u8bb8\u4fee\u6539<\/p>\n
3\u3001\u5982\u679c\u9700\u8981\u4fee\u6539\u4e3b\u7801\uff0c\u5fc5\u987b\u5148\u5220\u9664\uff0c\u7136\u540e\u91cd\u65b0\u63d2\u5165\u4e3b\u7801<\/p>\n
3\u3001\u63d2\u5165\u64cd\u4f5c<\/h5>\n
1\u3001\u7528PUT\u8bed\u53e5\u5b9e\u73b0<\/p>\n
2\u3001\u6b65\u9aa4<\/p>\n
\u9996\u5148\u7528\u5bbf\u4e3b\u8bed\u8a00\u5728\u5de5\u4f5c\u7a7a\u95f4\u4e2d\u5efa\u7acb\u65b0\u5143\u7ec4\n\u7136\u540e\u7528 PUT \u8bed\u53e5\u628a\u8be5\u5143\u7ec4\u5b58\u5165\u6307\u5b9a\u7684\u5173\u7cfb\u4e2d<\/code><\/pre>\n
3\u3001PUT\u8bed\u53e5\u53ea\u5bf9\u4e00\u4e2a\u5173\u7cfb\u64cd\u4f5c\uff0c\u8868\u8fbe\u5f0f\u5fc5\u987b\u4e3a\u5355\u4e2a\u5173\u7cfb\u540d\u5b57<\/p>\n
4\u3001\u4f8b\u5b50<\/p>\n
\"image-20230822224459457\"<\/div><\/p>\n
4\u3001\u5220\u9664<\/h5>\n
1\u3001\u4f7f\u7528DELETE\u8bed\u53e5<\/p>\n
2\u3001\u6b65\u9aa4<\/p>\n
\u7528HOLD\u8bed\u53e5\u628a\u5220\u9664\u7684\u5143\u7ec4\u4ece\u6570\u636e\u5e93\u8bfb\u53d6\u5230\u5de5\u4f5c\u7a7a\u95f4\u4e2d\n\u7528DELETE\u8bed\u53e5\u5220\u9664\u8be5\u5143\u7ec4<\/code><\/pre>\n
3\u3001\u4f8b\u5b50<\/p>\n
\"image-20230822224745571\"<\/div><\/p>\n
4\u3001\u4f8b\u5b50<\/p>\n
\"image-20230822225024628\"<\/div><\/p>\n
2.5.2\u3001\u5143\u7ec4\u5173\u7cfb\u6f14\u7b97<\/h3>\n
1\u3001\u5047\u8bbe\u5173\u7cfb\uff08\u57fa\u6570\uff09\u662f\u65e0\u9650\u7684\uff0c\u518d\u8fdb\u884c\u6f14\u7b97\u505a\u9002\u5f53\u8c03\u6574\uff0c\u8981\u4fdd\u8bc1\u6f14\u7b97\u4e2d\u6bcf\u4e2a\u6f14\u7b97\u7684\u516c\u5f0f\u5fc5\u987b\u6709\u9650<\/p>\n
2\u3001\u8868\u8fbe\u5f0f<\/p>\n
\"image-20230822230121512\"<\/div><\/p>\n
\u5176\u4e2dt\uff1a\u662f\u5143\u7ec4\u53d8\u91cf<\/p>\n
1\u3001\u539f\u5b50\u516c\u5f0f\u6709\u4e09\u7c7b<\/h4>\n
1\u3001R(t)<\/h5>\n
1\u3001R\u662f\u5173\u7cfb\u540d<\/p>\n
2\u3001t\u662f\u5143\u7ec4\u53d8\u91cf<\/p>\n
3\u3001\u610f\u601d\uff1at\u662fR\u4e2d\u7684\u5143\u7ec4<\/p>\n
2\u3001t[i]\u03b8u[j]<\/h5>\n
1\u3001t\u548cu\u662f\u5143\u7ec4\u53d8\u91cf<\/p>\n
2\u3001\u03b8\u662f\u7b97\u672f\u6bd4\u8f83\u8fd0\u7b97\u7b26\uff0c<\/p>\n
3\u3001t[i]\u03b8u[j]\uff1a\u8868\u793a\u65ad\u8a00<\/p>\n
4\u3001\u5185\u5bb9\u662f\uff1a\u5143\u7ec4t\u7684\u7b2ci\u4e2a\u5206\u91cf\u4e0e\u5143\u7ec4u\u7684\u7b2cj\u4e2a\u5206\u91cf\u6ee1\u8db3\u6bd4\u8f83\u5173\u7cfb\u03b8<\/p>\n
5\u3001\u4f8b\u5b50\uff1at[2]<u[3]    #\u5176\u4e2dt[2]\u8868\u793a\u7b2c\u4e00\u884c\u7684\u7b2c2\u4e2a\u6570\u636e\uff0cu[3]\u8868\u793a\u7684\u662fu\u7b2c\u4e00\u884c\u7684\u7b2c\u4e09\u4e2a\u6570\u636e<\/p>\n
3\u3001t[i]\u03b8c\u6216c\u03b8t[i]<\/h5>\n
1\u3001c\u662f\u5e38\u91cf<\/p>\n
2\u3001\u5185\u5bb9\u662f\uff1at\u7684\u7b2ci\u4e2a\u5206\u91cf\u4e0e\u5e38\u91cfc\u6ee1\u8db3\u6bd4\u8f83\u5173\u7cfb\u03b8<\/p>\n
2\u3001\u81ea\u7531\u5143\u7ec4\u53d8\u91cf\/\u7ea6\u675f\u5143\u7ec4\u53d8\u91cf<\/h4>\n
1\u3001\u81ea\u7531\u5143\u7ec4\u53d8\u91cf<\/h5>\n
1\u3001\u6ca1\u6709\u5168\u79f0\u91cf\u8bcd\u3001\u6216\u5b58\u5728\u91cf\u8bcd\u7ea6\u675f<\/p>\n
2\u3001\u7ea6\u675f\u5143\u7ec4\u53d8\u91cf<\/h5>\n
1\u3001\u6709\u5168\u79f0\u91cf\u8bcd\u6216\u5b58\u5728\u91cf\u8bcd\u7684\u7ea6\u675f<\/p>\n
3\u3001\u516c\u5f0f\u53ef\u4ee5\u9012\u5f52\u5b9a\u4e49\u5982\u4e0b<\/h4>\n
1\/2\u3001\u5185\u5bb9<\/h5>\n
\"image-20230822231928895\"<\/div><\/p>\n
2\u3001\u4e0e\uff1a1\u30012\u540c\u65f6\u4e3a\u771f\uff0c\u624d\u4e3a\u771f<\/p>\n
3\u3001\u6216\uff1a1\u30012\u5176\u4e2d\u4e00\u4e2a\u6170\u95ee\u771f\u5c31\u662f\u771f\uff0c\u4e24\u4e2a\u662f\u5047\u624d\u662f\u5047<\/p>\n
4\u3001\u975e\uff1a1\u4e3a\u771f\u30012\u5c31\u4e3a\u5047\uff0c\u53cd\u4e4b\u4e00\u6837<\/p>\n
3\u3001\u82e5\u03c6\u662f\u516c\u5f0f\u5219\u2203t(\u222e)\u4e5f\u662f\u516c\u5f0f<\/h5>\n
1\u3001\u2203\uff1a\u5b58\u5728\u91cf\u8bcd\u7b26\u53f7<\/p>\n
2\u3001\u2203t(\u222e)\u8868\u793a\uff1a\u82e5\u6709\u4e00\u4e2at\u4f7f\u222e\u4e3a\u771f\uff0c\u5219\u2203t(\u222e)\u4e3a\u771f\uff0c\u5426\u5219\u4e3a\u5047<\/p>\n
4\u3001 \u516c\u5f0f<\/h5>\n
1\u3001\u5185\u5bb9<\/p>\n
\"image-20230822233418641\"<\/div><\/p>\n
2\u3001\u4e24\u4e2a\u771f\u624d\u4e3a\u771f\uff0c\u4e00\u4e2a\u5047\u5c31\u662f\u5047<\/p>\n
4\u3001\u5143\u7ec4\u6f14\u7b97\u516c\u5f0f\u4e2d\uff0c\u5404\u79cd\u8fd0\u7b97\u7b26\u7684\u4f18\u5148\u6b21\u5e8f<\/h4>\n
1\u3001\u5185\u5bb9<\/h5>\n
1\u3001\u7b97\u672f\u6bd4\u8f83\u8fd0\u7b97\u7b26\u6700\u9ad8<\/p>\n
2\u3001\u91cf\u8bcd\u6b21\u4e4b\uff0c\u4e14\u2203\u7684\u4f18\u5148\u7ea7\u9ad8\u4e8e\u5168\u79f0\u91cf\u8bcd\u7684\u4f18\u5148\u7ea7<\/p>\n
3\u3001\u903b\u8f91\u8fd0\u7b97\u7b26\u6700\u4f4e\uff0c\u4e14\u975e\u7684\u4f18\u5148\u7ea7\u9ad8\u4e8e\u2227\uff08\u4e0e\uff09\u7684\u4f18\u5148\u7ea7\uff0c\u2227\uff08\u4e0e\uff09\u7684\u4f18\u5148\u7ea7\u9ad8\u4e8e\u2228 \uff08\u6216\uff09\u7684\u4f18\u5148\u7ea7<\/p>\n
4\u3001\u52a0\u62ec\u53f7\u65f6\uff0c\u62ec\u53f7\u4e2d\u7684\u4f18\u5148\u7ea7\uff0c\u540c\u4e00\u62ec\u53f7\u4e2d\uff0c\u9075\u5b88\u2460\u3001\u2461\u3001\u2462<\/p>\n
2\u3001\u6ce8\u610f<\/h5>\n
1\u3001\u6709\u9650\u6b21\u7b2c\u4f7f\u7528\u4e0a\u8ff0\u4e94\u6761\u89c4\u5219\u5f97\u5230\u7684\u516c\u5f0f\u662f\uff0c\u5143\u7ec4\u516c\u5f0f\uff0c\u5426\u5219\u4e0d\u662f\u5143\u7ec4\u5173\u7cfb\u6f14\u7b97\u516c\u5f0f<\/p>\n
3\u3001\u5173\u7cfb\u4ee3\u6570\u8fd0\u7b97\u2014>\u5173\u7cfb\u8868\u8fbe\u5f0f<\/h5>\n
1\u3001\u5173\u7cfb\u4ee3\u6570\u8fd0\u7b97\u53ef\u4ee5\u7528\u5173\u7cfb\u6f14\u7b97\u8868\u8fbe\u5f0f\u6765\u8868\u793a\uff08\u76f8\u53cd\u4e5f\u53ef\u4ee5\uff09\uff0c\u4e0b\u9762\u7528\u5173\u7cfb\u6f14\u7b97\u7b26\u8868\u8fbe\u5f0f\u6765\u8868\u793a\u4e94\u79cd\u57fa\u672c\u8fd0\u7b97<\/p>\n
2\u3001\u56fe\u793a\u516c\u5f0f<\/p>\n
\"image-20230823200306482\"<\/div><\/p>\n
3\u3001\u4f8b\u5b50<\/p>\n
\"image-20230823201209444\"<\/div><\/p>\n
5\u3001\u5b89\u5168\u9650\u5236<\/h4>\n
1\u3001\u5185\u5bb9<\/h5>\n
1\u3001\u4ee5\u4e0a\u5b9a\u4e49\u7684\u5173\u7cfb\u6f14\u7b97\u5141\u8bb8\u65e0\u9650\u5173\u7cfb\uff0c\u4f46\u662f\u5fc5\u987b\u6392\u9664\u65e0\u610f\u4e49\u7684\u8868\u8fbe\u5f0f<\/strong><\/p>\n
2\u3001\u5b89\u5168\u8868\u8fbe\u5f0f\uff1a\u4e0d\u751f\u6210\u65e0\u9650\u5173\u7cfb\u7684\u8868\u8fbe\u5f0f\uff0c\u91c7\u53d6\u5b89\u5168\u9650\u5236<\/p>\n
3\u3001\u5b89\u5168\u9650\u5236\uff1a\u5b9a\u4e49\u6709\u9650\u7684\u96c6\u5408\uff0c\u5fc5\u987b\u5728\u5728\u9650\u5b9a\u7684\u8303\u56f4\u5185\u7684\u67e5\u8be2\u6570\u636e<\/p>\n
2.5.3\u3001\u57df\u5173\u7cfb\u6f14\u7b97\u8bed\u8a00QBE<\/h3>\n
1\u3001\u5185\u5bb9<\/h4>\n
1\u3001\u662f\u53e6\u4e00\u79cd\u5f62\u5f0f\u7684\u57df\u5173\u7cfb\u6f14\u7b97<\/p>\n
2\u30011975\u5e74\u88ab\u8e22\u51fa\uff0c1978\u5e74\u5728IBM370\u4e0a\u5f97\u4ee5\u5b9e\u73b0<\/p>\n
3\u3001\u57fa\u4e8e\u5c4f\u5e55\u8868\u683c\u7684\u67e5\u8be2\u8bed\u53e5<\/p>\n
4\u3001QBE\u4e2d\u7528\u5b9e\u4f8b\u5143\u7d20\u6765\u67e5\u8be2\u7ed3\u679c\u53ef\u80fd\u7684\u60c5\u51b5\uff0c\u793a\u4f8b\u5143\u7d20\u5b9e\u8d28\u4e0a\u662f\u57df\u53d8\u91cf<\/p>\n
2\u3001QBE\u64cd\u4f5c\u6846\u67b6<\/h4>\n
1\u3001\u56fe\u793a<\/p>\n
\"image-20230823204306955\"<\/div><\/p>\n
3\u3001\u67e5\u8be2\u64cd\u4f5c<\/h4>\n
1\u3001\u7b80\u5355\u67e5\u8be2<\/h5>\n
1\u3001\u64cd\u4f5c\u6b65\u9aa4<\/p>\n
\"image-20230823205121240\"<\/div><\/p>\n
2\u3001\u6ce8\u610f\u8868\u683c\u4e2d\u6709\u4e0b\u5212\u7ebf\u7684\u662f\u4e00\u5b9a\u8981\u6709\u8be5\u5143\u7d20<\/p>\n
3\u3001\u6ca1\u6709\u4e0b\u5212\u7ebf\u7684\u8868\u793a\u6761\u4ef6<\/p>\n
4\u3001\u8bf4\u660e<\/p>\n
\u2460\u53ef\u4ee5\u4f7f\u7528\u6bd4\u8f83\u8fd0\u7b97\u7b26<\/p>\n
\u2461\u5176\u4e2d=\u53ef\u4ee5\u7701\u7565<\/p>\n
2\u3001\u6761\u4ef6\u67e5\u8be2<\/h5>\n
1\u3001\u5c31\u662f\u5e26\u6bd4\u8f83\u8fd0\u7b97\u7b26\u7b49\u6761\u4ef6<\/p>\n
2\u3001\u4e24\u4e2a\u6761\u4ef6\u5199\u4e00\u884c\uff0c\u5c31\u662f\u5e76\u7684\u5173\u7cfb<\/p>\n
3\u3001\u4e24\u4e2a\u6761\u4ef6\u5199\u4e0d\u540c\u884c\uff0c\u4e14\u67e5\u8be2\u6761\u4ef6\u4e0d\u4e00\u6837\uff0c\u5c31\u662f\u6216\u7684\u5173\u7cfb<\/p>\n
4\u3001\u4f8b\u5b50<\/p>\n
\"image-20230823212512485\"<\/div><\/p>\n
5\u3001\u4f8b\u5b502<\/p>\n
\"image-20230823213138285\"<\/div><\/p>\n
\u2460\u8bbe\u8ba1\u5230\u4e24\u8868\u8fde\u63a5<\/p>\n
6\u3001\u4f8b\u5b503<\/p>\n
\"image-20230823214521047\"<\/div><\/p>\n
\u2460\u5bf9\u4e00\u4e2a\u8868\u683c\u4e2d\u7684\u5c5e\u6027\u53d6\u53cd\uff0c\u5c31\u7528\u8868\u975e\u7b26\u53f7<\/p>\n
3\u3001\u805a\u5408\u51fd\u6570<\/h5>\n
1\u3001\u63d0\u4f9b\u4e00\u4e9b\u5305\u88c5\u597d\u7684\u51fd\u6570\u4f9b\u4f7f\u7528<\/p>\n
2\u3001\u5185\u5bb9<\/p>\n
\"image-20230823214648251\"<\/div><\/p>\n
3\u3001\u4f8b\u5b50<\/p>\n
\"image-20230823215128451\"<\/div><\/p>\n
4\u3001\u5bf9\u67e5\u8be2\u7ed3\u679c\u6392\u5e8f<\/h5>\n
1\u3001\u5347\u5e8f<\/p>\n
AO(i).\n#i\u4e3a\u4f18\u5148\u7ea7<\/code><\/pre>\n
2\u3001\u964d\u5e8f<\/p>\n
DO(i).\n#i\u4e3a\u4f18\u5148\u7ea7<\/code><\/pre>\n
3\u3001\u4f8b\u5b50<\/p>\n
\"image-20230823220139916\"<\/div><\/p>\n
4\u3001\u66f4\u65b0\u64cd\u4f5c<\/h4>\n
1\u3001\u4fee\u6539\u64cd\u4f5c<\/h5>\n
1\u3001\u683c\u5f0f<\/p>\n
U.<\/code><\/pre>\n
2\u3001\u4e3b\u7801\u4e0d\u5141\u8bb8\u4fee\u6539\uff0c\u8981\u4fee\u6539\u4e3b\u7801\uff0c\u548c\u963f\u5c14\u6cd5\u8bed\u8a00\u4e00\u6837<\/p>\n
3\u3001\u4f8b\u5b50<\/p>\n
\"image-20230823220552727\"<\/div><\/p>\n
4\u3001\u4f8b\u5b50<\/p>\n
\"image-20230823221627596\"<\/div><\/p>\n
2\u3001\u63d2\u5165\u64cd\u4f5c<\/h5>\n
1\u3001\u683c\u5f0f<\/p>\n
I.<\/code><\/pre>\n
2\u3001\u65b0\u63d2\u5165\u7684\u5143\u7ec4\u5fc5\u987b\u6709\u7801\u503c\uff08\u4e3b\u7801\u5fc5\u987b\u6709\u503c\uff09\u3001\u5176\u4ed6\u5c5e\u6027\u503c\u53ef\u4ee5\u4e3a\u7a7a<\/p>\n
3\u3001\u4f8b\u5b50<\/p>\n
\"image-20230823221819462\"<\/div><\/p>\n
3\u3001\u5220\u9664\u64cd\u4f5c<\/h5>\n
1\u3001\u683c\u5f0f<\/p>\n
D.<\/code><\/pre>\n
2\u3001\u5220\u9664\u5c31\u662f\u6574\u6761\u8bb0\u5f55\uff0c\u6216\u8868\u683c\u5220\u9664<\/p>\n
3\u3001\u5982\u679c\u5355\u72ec\u5220\u9664\u4e00\u4e2a\u5c5e\u6027\uff0c\u90a3\u8981\u7528update\u64cd\u4f5c<\/p>\n
4\u3001\u76f8\u5173\u5bf9\u7167\u7684\u5176\u4ed6\u8868\u4e5f\u5e94\u8be5\u5220\u9664\uff08\u4f8b\u5982\u5b66\u751f\u9000\u5b66\u4e86\uff0c\u4f4f\u5bbf\u3001\u8bfe\u7a0b\u3001\u7b49\u8868\u90fd\u5e94\u8be5\u5220\u9664\uff09\uff0c\u4fdd\u8bc1\u6570\u636e\u7684\u5b8c\u6574\u6027<\/p>\n
5\u3001\u4f8b\u5b50<\/p>\n
\"image-20230823222250485\"<\/div><\/p>\n
\u7b2c\u4e09\u7ae0\u3001\u5173\u7cfb\u6570\u636e\u5e93\u6807\u51c6\u8bed\u8a00SQL<\/h1>\n","protected":false},"excerpt":{"rendered":"
\u7b2c\u4e8c\u7ae0\u3001\u5173\u7cfb\u6570\u636e\u5e93 \u5173\u7cfb\u6570\u636e\u5e93\u7b80\u4ecb 2.1\u3001\u5173\u7cfb\u6570\u636e\u7ed3\u6784\u53ca\u5f62\u5f0f\u5316\u5b9a\u4e49 2.1.1\u3001\u5173\u7cfb 1\u3001\u5355\u4e00\u7684\u6570\u636e\u7ed3\u6784\u2014\u2014 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[42],"tags":[],"class_list":["post-5771","post","type-post","status-publish","format-standard","hentry","category-42"],"_links":{"self":[{"href":"http:\/\/zyg.luchers.cn\/index.php\/wp-json\/wp\/v2\/posts\/5771","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/zyg.luchers.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/zyg.luchers.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/zyg.luchers.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/zyg.luchers.cn\/index.php\/wp-json\/wp\/v2\/comments?post=5771"}],"version-history":[{"count":1,"href":"http:\/\/zyg.luchers.cn\/index.php\/wp-json\/wp\/v2\/posts\/5771\/revisions"}],"predecessor-version":[{"id":5772,"href":"http:\/\/zyg.luchers.cn\/index.php\/wp-json\/wp\/v2\/posts\/5771\/revisions\/5772"}],"wp:attachment":[{"href":"http:\/\/zyg.luchers.cn\/index.php\/wp-json\/wp\/v2\/media?parent=5771"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/zyg.luchers.cn\/index.php\/wp-json\/wp\/v2\/categories?post=5771"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/zyg.luchers.cn\/index.php\/wp-json\/wp\/v2\/tags?post=5771"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}