\u6578\u64da\u67e5\u8a62\uff0c\u662f\u6578\u64da\u5eab\u64cd\u4f5c\u4e2d\u6700\u4e3b\u8981\u7684\u529f\u80fd\u4e4b\u58f9;\u6709\u6642\u5019\u6578\u64da\u5eab\u67e5\u8a62\u6027\u80fd\u7684\u597d\u58de\uff0c\u76f4\u63a5\u95dc\u7cfb\u5230\u6578\u64da\u5eab\u7684\u904b\u884c\u6548\u7387\uff0c\u95dc\u7cfb\u5230\u6578\u64da\u5eab\u7684\u9078\u578b\u3002\u4e0b\u9762\u7b46\u8005\u4e0d\u8ac7\u5927\u9053\u7406\uff0c\u53ea\u662f\u5c0d\u5176\u4e2d\u5c0d\u58f9\u4e9b\u5e73\u6642\u5927\u5bb6\u5bb9\u6613\u5ffd\u7565\u7684\u67e5\u8a62\u5c0f\u6280\u5de7\u505a\u58f9\u4e9b\u7e3d\u7d50\u3002\u6216\u8a31\u5927\u5bb6\u53ef\u80fd\u6b63\u5728\u70ba\u6b64\u72af\u6101\u5462?<\/p>\n
\u3000\u3000\u7b2c\u58f9\u500b\u6280\u5de7\uff1a\u5229\u7528\u9023\u63a5\u7b26\u9023\u63a5\u591a\u500b\u5b57\u6bb5<\/p>\n
\u3000\u3000\u5982\u5728\u54e1\u5de5\u57fa\u672c\u4fe1\u606f\u8868\u4e2d\uff0c\u6709\u54e1\u5de5\u59d3\u540d\u3001\u54e1\u5de5\u8077\u4f4d\u3001\u51fa\u8eab\u65e5\u671f\u7b49\u7b49\u3002\u5982\u679c\u73fe\u5728\u8996\u5716\u4e2d\u9019\u4e09\u500b\u5b57\u6bb5\u986f\u793a\u5728\u540c\u58f9\u500b\u5b57\u6bb5\u4e2d\uff0c\u4e26\u4e14\u4e2d\u9593\u6709\u5206\u5272\u7b26\u3002\u5982\u6211\u73fe\u5728\u60f3\u986f\u793a\u7684\u7d50\u679c\u70ba\u201c\u7d93\u7406Victor\u51fa\u8eab\u65bc1976\u5e745\u67083\u65e5\u201d\u3002\u9019\u8a72\u5982\u4f55\u8655\u7406\u5462?\u5176\u5be6\uff0c\u9019\u662f\u6bd4\u8f03\u7c21\u55ae\u7684\uff0c\u6211\u5011\u53ef\u4ee5\u5728Select\u67e5\u8a62\u8a9e\u53e5\u4e2d\uff0c\u5229\u7528\u9023\u63a5\u7b26\u628a\u9019\u4e9b\u5b57\u6bb5\u9023\u63a5\u8d77\u4f86\u3002<\/p>\n
\u3000\u3000\u5982\u53ef\u4ee5\u9019\u9ebd\u5beb\u67e5\u8a62\u8a9e\u53e5\uff1a<\/p>\n
\u3000\u3000SELECT\u54e1\u5de5\u8077\u4f4d ||\u2019 \u2019 ||\u54e1\u5de5\u59d3\u540d||\u2019\u51fa\u8eab\u65bc\u2019||\u51fa\u8eab\u65e5\u671f as \u54e1\u5de5\u51fa\u8eab\u4fe1\u606f FROM \u54e1\u5de5\u57fa\u672c\u4fe1\u606f\u8868;<\/p>\n
\u3000\u3000\u901a\u904e\u9019\u689d\u8a9e\u53e5\u5c31\u53ef\u4ee5\u5be6\u73fe\u5982\u4e0a\u7684\u9700\u6c42\u3002\u4e5f\u5c31\u662f\u8aaa\uff0c\u6211\u5011\u5728\u5e73\u6642\u67e5\u8a62\u4e2d\uff0c\u53ef\u4ee5\u5229\u7528||\u9023\u63a5\u7b26\u628a\u58f9\u4e9b\u76f8\u95dc\u7684\u5b57\u6bb5\u9023\u63a5\u8d77\u4f86\u3002\u9019\u5728\u5831\u8868\u8996\u5716\u4e2d\u975e\u5e38\u7684\u6709\u7528\u3002\u5982\u7b46\u8005\u4ee5\u524d\u5728\u8a2d\u8a08\u5716\u66f8\u9928\u7ba1\u7406\u7cfb\u7d71\u7684\u6642\u5019\uff0c\u5728\u66f8\u7684\u57fa\u672c\u4fe1\u606f\u8655\u6709\u5716\u66f8\u7684\u51fa\u7248\u793e\u3001\u51fa\u7248\u5e8f\u5217\u865f\u7b49\u7b49\u5167\u5bb9\u3002\u4f46\u662f\uff0c\u6709\u6642\u6703\u5728\u6253\u5370\u5831\u8868\u7684\u6642\u5019\uff0c\u9700\u8981\u628a\u9019\u4e9b\u5b57\u6bb5\u5408\u4e26\u6210\u58f9\u500b\u5b57\u6bb5\u6253\u5370\u3002\u70ba\u6b64\uff0c\u5c31\u9700\u8981\u5229\u7528\u9019\u500b\u9023\u63a5\u7b26\u628a\u9019\u4e9b\u5b57\u6bb5\u9023\u63a5\u8d77\u4f86\u3002\u800c\u4e14\uff0c\u5229\u7528\u9023\u63a5\u7b26\u9084\u53ef\u4ee5\u5728\u5b57\u6bb5\u4e2d\u9593\u52a0\u5165\u58f9\u4e9b\u8aaa\u660e\u6027\u7684\u6587\u5b57\uff0c\u4ee5\u65b9\u4fbf\u5927\u5bb6\u95b1\u8b80\u3002\u5982\u4e0a\u9762\u6211\u5728\u54e1\u5de5\u8077\u4f4d\u8207\u54e1\u5de5\u59d3\u540d\u4e4b\u9593\u52a0\u5165\u4e86\u7a7a\u683c;\u4e26\u4e14\u5728\u54e1\u5de5\u59d3\u540d\u8207\u51fa\u8eab\u65e5\u671f\u4e4b\u9593\u52a0\u5165\u4e86\u51fa\u8eab\u65bc\u5e7e\u500b\u8a3b\u91cb\u6027\u7684\u6587\u5b57\u3002\u9019\u4e9b\u529f\u80fd\u770b\u8d77\u4f86\u6bd4\u8f03\u5c0f\uff0c\u4f46\u662f\u537b\u53ef\u4ee5\u5927\u5927\u7684\u63d0\u9ad8\u5167\u5bb9\u7684\u53ef\u8b80\u6027\u3002\u9019\u4e5f\u662f\u6211\u5011\u5728\u6578\u64da\u5eab\u8a2d\u8a08\u904e\u7a0b\u4e2d\u9700\u8981\u95dc\u8a3b\u7684\u58f9\u500b\u5167\u5bb9\u3002<\/p>\n
\u3000\u3000\u7e3d\u4e4b\uff0c\u4ee4\u5f8c\u91c7\u7528\u9023\u63a5\u7b26\uff0c\u53ef\u4ee5\u63d0\u9ad8\u6211\u5011\u5831\u8868\u7684\u53ef\u8b80\u6027\u65bc\u9748\u6d3b\u6027\u3002<\/p>\n
\u3000\u3000\u7b2c\u4e8c\u500b\u6280\u5de7\uff1a\u53d6\u6d88\u91cd\u5fa9\u7684\u884c<\/p>\n
\u3000\u3000\u5982\u5728\u4eba\u4e8b\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0c\u6709\u54e1\u5de5\u57fa\u672c\u4fe1\u606f\u57fa\u672c\u8868\u3002\u5728\u9019\u5f35\u8868\u4e2d\uff0c\u53ef\u80fd\u6703\u6709\u90e8\u9580\u3001\u8077\u4f4d\u3001\u54e1\u5de5\u59d3\u540d\u3001\u8eab\u4efd\u8b49\u4ef6\u865f\u78bc\u7b49\u5b57\u6bb5\u3002\u82e5\u67e5\u8a62\u9019\u4e9b\u5167\u5bb9\uff0c\u53ef\u80fd\u4e0d\u6703\u6709\u91cd\u5fa9\u7684\u884c\u3002\u4f46\u662f\uff0c\u6211\u82e5\u60f3\u77e5\u9053\uff0c\u5728\u516c\u53f8\u5167\u90e8\u8a2d\u7f6e\u4e86\u54ea\u4e9b\u90e8\u9580\u8207\u8077\u4f4d\u7684\u6642\u5019\uff0c\u4e26\u4e14\u9019\u4e9b\u90e8\u9580\u8207\u8077\u4f4d\u914d\u7f6e\u4e86\u76f8\u95dc\u4eba\u54e1\u3002\u6b64\u6642\uff0c\u53c8\u8a72\u5982\u4f55\u67e5\u8a62\u5462?<\/p>\n
\u3000\u3000\u82e5\u6211\u73fe\u5728\u76f4\u63a5\u67e5\u8a62\u90e8\u9580\u8868\uff0c\u5176\u53ef\u4ee5\u77e5\u9053\u7cfb\u7d71\u4e2d\u5177\u9ad4\u8a2d\u7f6e\u4e86\u54ea\u4e9b\u90e8\u9580\u8207\u8077\u4f4d\u3002\u4f46\u662f\uff0c\u5f88\u6709\u53ef\u80fd\u9019\u4e9b\u90e8\u9580\u6216\u8005\u8077\u4f4d\u7531\u65bc\u4eba\u4e8b\u8b8a\u52d5\u7684\u95dc\u7cfb\uff0c\u73fe\u5728\u5df2\u7d93\u6c92\u6709\u4eba\u4e86\u3002\u6240\u4ee5\uff0c\u9019\u88cf\u67e5\u8a62\u51fa\u4f86\u7684\u662f\u6240\u6709\u7684\u90e8\u9580\u8207\u8077\u4f4d\u4fe1\u606f\uff0c\u800c\u4e0d\u80fd\u5920\u4fdd\u8b49\u9019\u500b\u90e8\u9580\u6216\u8005\u8077\u4f4d\u58f9\u5b9a\u6709\u8077\u54e1\u5b58\u5728\u3002\u4e5f\u5c31\u662f\u8aaa\uff0c\u9019\u4e0d\u80fd\u5920\u6eff\u8db3\u65bc\u6211\u5011\u4e0a\u9762\u7684\u8981\u6c42\u3002<\/p>\n
\u3000\u3000\u82e5\u6211\u73fe\u5728\u76f4\u63a5\u5f9e\u54e1\u5de5\u4fe1\u606f\u8868\u4e2d\u67e5\u8a62\uff0c\u96d6\u7136\u53ef\u4ee5\u4fdd\u8b49\u6240\u67e5\u8a62\u51fa\u4f86\u7684\u90e8\u9580\u8207\u8077\u4f4d\u4fe1\u606f\uff0c\u58f9\u5b9a\u6709\u54e1\u5de5\u4fe1\u606f\u7684\u5b58\u5728\u3002\u4f46\u662f\uff0c\u6b64\u6642\u67e5\u8a62\u51fa\u4f86\u7684\u90e8\u9580\u8207\u8077\u4f4d\u4fe1\u606f\u6703\u6709\u91cd\u5fa9\u7684\u884c\u3002\u5982\u91c7\u8cfc\u90e8\u9580\u5206\u5de5\u5408\u4f5c\uff0c\u53ef\u80fd\u6703\u6709\u91c7\u8cfc\u91c7\u8cfc\u5c0f\u7d44\u9577\u3002\u6b64\u6642\uff0c\u5728\u67e5\u8a62\u51fa\u4f86\u7684\u90e8\u9580\u8207\u8077\u4f4d\u7684\u4fe1\u606f\u4e2d\uff0c\u5c31\u6703\u6709\u4e09\u689d\u91cd\u5fa9\u7684\u8a18\u9304\u3002<\/p>\n
\u3000\u3000\u6240\u4ee5\uff0c\u4ee5\u4e0a\u5169\u7a2e\u8655\u7406\u65b9\u5f0f\uff0c\u90fd\u4e0d\u80fd\u5920\u767e\u5206\u4e4b\u767e\u7684\u6eff\u8db3\u4f01\u696d\u7528\u6236\u7684\u9700\u6c42\u3002\u6b64\u6642\uff0c\u6211\u5011\u5176\u5be6\u53ef\u4ee5\u5229\u7528\u58f9\u500bDISTINCT\u51fd\u6578\uff0c\u4f86\u6d88\u9664\u5176\u4e2d\u67e5\u8a62\u51fa\u4f86\u7684\u91cd\u5fa9\u884c\u3002<\/p>\n
\u3000\u3000\u5982\u6211\u5011\u53ef\u4ee5\u5229\u7528SELECT DISTINCT \u90e8\u9580\u4fe1\u606f\uff0c\u8077\u4f4d\u4fe1\u606f FROM \u54e1\u5de5\u57fa\u672c\u4fe1\u606f\u8868\u3002\u901a\u904e\u9019\u689d\u52a0\u4e86DISTINCT\u7d04\u675f\u7684\u67e5\u8a62\u8a9e\u53e5\uff0c\u4e0d\u4f46\u53ef\u4ee5\u67e5\u8a62\u51fa\u6240\u6709\u6709\u54e1\u5de5\u7684\u8077\u4f4d\u8207\u90e8\u9580\u4fe1\u606f\uff0c\u800c\u4e14\uff0c\u6703\u628a\u91cd\u5fa9\u7684\u8a18\u9304\u904e\u6ffe\u6389\uff0c\u5f9e\u800c\u63d0\u9ad8\u53ef\u95b1\u8b80\u6027\u3002<\/p>\n
\u3000\u3000\u6240\u4ee5\uff0c\u5728\u6578\u64da\u5eab\u8a2d\u8a08\u904e\u7a0b\u4e2d\uff0c\u7279\u5225\u662f\u5728\u67e5\u8a62\u8a9e\u53e5\u7684\u4f7f\u7528\u4e2d\uff0c\u9019\u500b\u51fd\u6578\u7279\u5225\u6709\u7528\u3002<\/p>\n
\u3000\u3000\u7b2c\u4e09\u500b\u6280\u5de7\uff1a\u52e4\u7528WHERE\u8a9e\u53e5<\/p>\n
\u3000\u3000\u6211\u5011\u90fd\u77e5\u9053\uff0c\u6578\u64da\u5eab\u67e5\u8a62\u6548\u7387\u9ad8\u4e0d\u9ad8\uff0c\u662f\u6211\u5011\u8a55\u50f9\u6578\u64da\u5eab\u8a2d\u8a08\u597d\u58de\u7684\u58f9\u500b\u91cd\u8981\u6a19\u6e96\u3002\u6bcb\u5eb8\u7f6e\u7591\uff0c\u5728\u6578\u64da\u5eab\u67e5\u8a62\u4e2d\u52e4\u7528Where\u689d\u4ef6\u8a9e\u53e5\uff0c\u662f\u63d0\u9ad8\u6578\u64da\u5eab\u67e5\u8a62\u6027\u80fd\u7684\u58f9\u500b\u5f88\u91cd\u8981\u7684\u624b\u6bb5\u4e4b\u58f9\u3002\u7279\u5225\u662f\u5728\u8a2d\u8a08\u5230\u6bd4\u8f03\u5927\u7684\u8868\u4e2d\u67e5\u8a62\u7b26\u5408\u689d\u4ef6\u7684\u8a18\u9304\u904e\u7a0b\u4e2d\uff0c\u5229\u7528WHERE\u689d\u4ef6\u8a9e\u53e5\u52a0\u4ee5\u9650\u5236\uff0c\u53ef\u4ee5\u5927\u5e45\u5ea6\u7684\u63d0\u9ad8\u67e5\u8a62\u7684\u97ff\u61c9\u901f\u5ea6\u3002<\/p>\n
\u3000\u3000\u5982\u5728\u5716\u66f8\u9928\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0c\u73fe\u5728\u6709\u4eba\u60f3\u67e5\u8a62\u201c\u8a3b\u518a\u6703\u8a08\u5e2b\u201d\u8f14\u5c0e\u7528\u66f8\u7684\u6642\u5019\uff0c\u96d6\u7136\u4e0d\u5728\u66f8\u7684\u985e\u5225\u6216\u8005\u540d\u7a31\u4e2d\u8f38\u5165\u201c\u8a3b\u518a\u6703\u8a08\u5e2b\u201d\uff0c\u5148\u67e5\u8a62\u51fa\u5168\u90e8\u7684\u7d00\u9304\uff0c\u7136\u5f8c\u518d\u58f9\u689d\u689d\u7684\u770b\u662f\u5426\u6709\u76f8\u95dc\u7684\u66f8\u7c4d\u4fe1\u606f\uff0c\u4e5f\u662f\u53ef\u884c\u7684\u3002\u4f46\u662f\uff0c\u9019\u9ebd\u8655\u7406\u7684\u8a71\uff0c\u58f9\u65b9\u9762\u7cfb\u7d71\u97ff\u61c9\u7684\u901f\u5ea6\u6703\u975e\u5e38\u7684\u6162\uff0c\u56e0\u70ba\u88cf\u9762\u8a18\u9304\u5f88\u591a\u3002\u53e6\u58f9\u65b9\u9762\uff0c\u67e5\u8a62\u7684\u7d50\u679c\u770b\u8d77\u4f86\u4e5f\u6703\u975e\u5e38\u7684\u982d\u75bc\u3002<\/p>\n
\u3000\u3000\u5176\u5be6\uff0c\u6211\u5011\u53ea\u9700\u8981\u5728\u67e5\u8a62\u4e2d\u52a0\u5165\u58f9\u4e9b\u67e5\u8a62\u7684\u53c3\u6578\uff0c\u5229\u7528Where\u689d\u4ef6\u8a9e\u53e5\u52a0\u4ee5\u9650\u5236\uff0c\u5247\u5373\u53ef\u4ee5\u63d0\u9ad8\u6578\u64da\u5eab\u97ff\u61c9\u7684\u901f\u5ea6\uff0c\u4e5f\u53ef\u4ee5\u627e\u51fa\u6700\u7b26\u5408\u7528\u6236\u9700\u6c42\u7684\u6578\u64da\u3002<\/p>\n
\u3000\u3000\u53e6\u5916\uff0c\u6211\u4e5f\u63a5\u89f8\u904e\u58f9\u4e9b\u5728Oracle\u6578\u64da\u5eab\u4e0a\u8a2d\u8a08\u7684\u5e73\u81fa\u578b\u7ba1\u7406\u8edf\u4ef6\uff0c\u4ed6\u5011\u53ef\u4ee5\u81ea\u5b9a\u7fa9\u76f8\u95dc\u7684\u5831\u8868\u3002\u5728\u5831\u8868\u8a2d\u8a08\u4e2d\uff0c\u53ea\u8981\u7528\u6236\u5728\u524d\u81fa\u8a2d\u8a08\u5e73\u81fa\u4e2d\uff0c\u9078\u4e2d\u201c\u5927\u8868\u67e5\u8a62\u201d\u7684\u8a71\uff0c\u5247\u9019\u500b\u5e73\u81fa\u6703\u5728\u751f\u6210\u5831\u8868\u7684\u6642\u5019\uff0c\u81ea\u52d5\u61c9\u7528Where\u689d\u4ef6\u8a9e\u53e5\uff0c\u4ee5\u63d0\u9ad8\u524d\u81fa\u7cfb\u7d71\u5f9e\u6578\u64da\u5eab\u67e5\u8a62\u6578\u64da\u7684\u6548\u7387\u3002<\/p>\n
\u3000\u3000\u6240\u4ee5\uff0c\u7b46\u8005\u8a8d\u70ba\u5728Oracle\u6578\u64da\u5eab\u7cfb\u7d71\u8a2d\u8a08\u4e2d\uff0c\u8981\u52e4\u65bc\u4f7f\u7528Where\u8a9e\u53e5\u3002\u5229\u7528Where\u8a9e\u53e5\u4f86\u63d0\u9ad8\u6578\u64da\u5eab\u67e5\u8a62\u7684\u6548\u7387\u3002<\/p>\n
\u3000\u3000\u7b2c\u56db\u500b\u6280\u5de7\uff1a\u9748\u6d3b\u4f7f\u7528COUNT\u51fd\u6578<\/p>\n
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\u3000\u3000\u7b2c\u4e94\u500b\u6280\u5de7\uff1a\u53ea\u67e5\u8a62\u6642\u5fc5\u9808\u7684\u5b57\u6bb5<\/p>\n
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\u3000\u3000\u82e5\u55ae\u5f9e\u6280\u8853\u4e0a\u8003\u616e\uff0c\u5169\u9019\u90fd\u662f\u53ef\u4ee5\u5be6\u73fe\u7684\uff0c\u4e0d\u6703\u6709\u591a\u5927\u7684\u96e3\u5ea6\u3002\u4f46\u662f\uff0c\u82e5\u662f\u5f9e\u6578\u64da\u5eab\u6027\u80fd\u4e0a\u8003\u616e\u5728\uff0c\u5247\u9084\u662f\u91c7\u7528\u4e0d\u540c\u7684\u8996\u5716\u4f86\u5be6\u73fe\u4e0d\u540c\u7684\u9700\u6c42\u70ba\u597d\u3002<\/p>\n
\u3000\u3000\u58f9\u65b9\u9762\uff0c\u82e5\u5f9e\u5b89\u5168\u65b9\u9762\u8b1b\uff0c\u5247\u53ef\u4ee5\u6839\u64da\u4e0d\u540c\u7684\u8996\u5716\u4f86\u63a7\u5236\u76f8\u95dc\u7684\u8a2a\u554f\u6b0a\u9650\u3002\u53ef\u898b\uff0c\u628a\u8996\u5716\u7d30\u5316\uff0c\u5728\u6b0a\u9650\u63a7\u5236\u4e0a\u5247\u6703\u66f4\u52a0\u7684\u9748\u6d3b\u3002<\/p>\n
\u3000\u3000\u53e6\u58f9\u65b9\u9762\uff0c\u6578\u64da\u7684\u67e5\u8a62\u6548\u7387\uff0c\u8ddf\u6578\u64da\u5167\u5bb9\u7684\u591a\u5c11\u4e5f\u6709\u975e\u5e38\u5bc6\u5207\u7684\u95dc\u7cfb\u3002\u5982\u5728\u67e5\u8a62\u54e1\u5de5\u5408\u540c\u5230\u671f\u4fe1\u606f\u7684\u6642\u5019\uff0c\u58f9\u822c\u4e0d\u9700\u8981\u54e1\u5de5\u7684\u5730\u5740\u4fe1\u606f\u7b49\u7b49\u3002\u82e5\u628a\u9019\u500b\u4fe1\u606f\u4e5f\u67e5\u8a62\u51fa\u4f86\u7684\u8a71\uff0c\u7531\u65bc\u9019\u500b\u5b57\u6bb5\u6bd4\u8f03\u9577\uff0c\u5c31\u6703\u82b1\u8cbb\u6bd4\u8f03\u9577\u7684\u6642\u9593\u3002\u6240\u4ee5\uff0c\u5728\u6578\u64da\u5eab\u8a2d\u8a08\u4e2d\uff0c\u6211\u5011\u8981\u5b78\u6703\u6839\u64da\u7528\u6236\u4e0d\u540c\u7684\u9700\u6c42\uff0c\u8a2d\u8a08\u4e0d\u540c\u7684\u8996\u5716\u3002\u96d6\u7136\u53ef\u80fd\u9019\u5728\u8a2d\u8a08\u7684\u6642\u5019\u6703\u6bd4\u8f03\u82b1\u6642\u9593\uff0c\u4f46\u662f\uff0c\u5728\u78ba\u53ef\u4ee5\u63d0\u9ad8\u6578\u64da\u5eab\u7684\u6027\u80fd\u8207\u5b89\u5168\u6027\u3002\u9019\u7b46\u751f\u610f\u9084\u662f\u5283\u5f97\u4f86\u7684\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
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||\u54e1\u5de5\u59d3\u540d||\u2019\u51fa\u8eab\u65bc\u2019||\u51fa\u8eab\u65e5\u671f as \u54e1\u5de5\u51fa\u8eab\u4fe1\u606f FROM \u54e1\u5de5\u57fa\u672c\u4fe1\u606f\u8868; 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