{"id":93952,"date":"2024-10-19T18:17:16","date_gmt":"2024-10-19T10:17:16","guid":{"rendered":"https:\/\/server.hk\/cnblog\/93952\/"},"modified":"2024-10-19T18:17:17","modified_gmt":"2024-10-19T10:17:17","slug":"oracle-join%e7%9a%84%e5%af%a6%e9%9a%9b%e6%87%89%e7%94%a8%e4%bb%a3%e7%a2%bc%e4%bb%8b%e7%b4%b9","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/93952\/","title":{"rendered":"Oracle join\u7684\u5be6\u969b\u61c9\u7528\u4ee3\u78bc\u4ecb\u7d39"},"content":{"rendered":"

Oracle Join\u7684\u5be6\u969b\u61c9\u7528\u4ee3\u78bc\u4ecb\u7d39<\/h1>\n

\u5728\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0cJoin\u64cd\u4f5c\u662f\u7528\u4f86\u5f9e\u5169\u500b\u6216\u591a\u500b\u8868\u4e2d\u6839\u64da\u76f8\u95dc\u7684\u5217\u4f86\u67e5\u8a62\u6578\u64da\u7684\u95dc\u9375\u6280\u8853\u3002Oracle\u6578\u64da\u5eab\u63d0\u4f9b\u4e86\u591a\u7a2eJoin\u985e\u578b\uff0c\u5305\u62ec\u5167\u90e8Join\u3001\u5916\u90e8Join\u3001\u4ea4\u53c9Join\u7b49\u3002\u672c\u6587\u5c07\u4ecb\u7d39\u9019\u4e9bJoin\u7684\u5be6\u969b\u61c9\u7528\uff0c\u4e26\u63d0\u4f9b\u76f8\u61c9\u7684\u4ee3\u78bc\u793a\u4f8b\u3002<\/p>\n

1. \u5167\u90e8Join (INNER JOIN)<\/h2>\n

\u5167\u90e8Join\u662f\u6700\u5e38\u7528\u7684Join\u985e\u578b\uff0c\u5b83\u8fd4\u56de\u5169\u500b\u8868\u4e2d\u5339\u914d\u7684\u884c\u3002\u7576\u6211\u5011\u9700\u8981\u5f9e\u591a\u500b\u8868\u4e2d\u7372\u53d6\u76f8\u95dc\u6578\u64da\u6642\uff0c\u5167\u90e8Join\u975e\u5e38\u6709\u7528\u3002<\/p>\n

SELECT a.employee_id, a.first_name, b.department_name\nFROM employees a\nINNER JOIN departments b ON a.department_id = b.department_id;<\/code><\/pre>\n
\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c\u6211\u5011\u5f9e\u54e1\u5de5\u8868\uff08employees\uff09\u548c\u90e8\u9580\u8868\uff08departments\uff09\u4e2d\u7372\u53d6\u54e1\u5de5ID\u3001\u59d3\u540d\u548c\u90e8\u9580\u540d\u7a31\u3002\u53ea\u6709\u7576\u54e1\u5de5\u7684\u90e8\u9580ID\u8207\u90e8\u9580\u8868\u4e2d\u7684\u90e8\u9580ID\u5339\u914d\u6642\uff0c\u8a72\u884c\u624d\u6703\u88ab\u8fd4\u56de\u3002<\/p>\n
2. \u5de6\u5916\u90e8Join (LEFT OUTER JOIN)<\/h2>\n
\u5de6\u5916\u90e8Join\u8fd4\u56de\u5de6\u8868\u4e2d\u7684\u6240\u6709\u884c\uff0c\u5373\u4f7f\u53f3\u8868\u4e2d\u6c92\u6709\u5339\u914d\u7684\u884c\u3002\u9019\u5728\u9700\u8981\u4fdd\u7559\u5de6\u8868\u6240\u6709\u6578\u64da\u7684\u60c5\u6cc1\u4e0b\u975e\u5e38\u6709\u7528\u3002<\/p>\n
SELECT a.employee_id, a.first_name, b.department_name\nFROM employees a\nLEFT OUTER JOIN departments b ON a.department_id = b.department_id;<\/code><\/pre>\n
\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c\u5373\u4f7f\u67d0\u4e9b\u54e1\u5de5\u6c92\u6709\u5206\u914d\u5230\u4efb\u4f55\u90e8\u9580\uff0c\u9019\u4e9b\u54e1\u5de5\u7684\u6578\u64da\u4ecd\u7136\u6703\u88ab\u8fd4\u56de\uff0c\u90e8\u9580\u540d\u7a31\u5c07\u986f\u793a\u70baNULL\u3002<\/p>\n
3. \u53f3\u5916\u90e8Join (RIGHT OUTER JOIN)<\/h2>\n
\u53f3\u5916\u90e8Join\u8207\u5de6\u5916\u90e8Join\u76f8\u53cd\uff0c\u5b83\u8fd4\u56de\u53f3\u8868\u4e2d\u7684\u6240\u6709\u884c\uff0c\u5373\u4f7f\u5de6\u8868\u4e2d\u6c92\u6709\u5339\u914d\u7684\u884c\u3002<\/p>\n
SELECT a.employee_id, a.first_name, b.department_name\nFROM employees a\nRIGHT OUTER JOIN departments b ON a.department_id = b.department_id;<\/code><\/pre>\n
\u9019\u500b\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u90e8\u9580\u7684\u6578\u64da\uff0c\u5373\u4f7f\u67d0\u4e9b\u90e8\u9580\u6c92\u6709\u4efb\u4f55\u54e1\u5de5\uff0c\u9019\u4e9b\u90e8\u9580\u7684\u540d\u7a31\u4ecd\u7136\u6703\u986f\u793a\u51fa\u4f86\uff0c\u54e1\u5de5ID\u548c\u59d3\u540d\u5c07\u986f\u793a\u70baNULL\u3002<\/p>\n
4. \u5168\u5916\u90e8Join (FULL OUTER JOIN)<\/h2>\n
\u5168\u5916\u90e8Join\u8fd4\u56de\u5169\u500b\u8868\u4e2d\u7684\u6240\u6709\u884c\uff0c\u7121\u8ad6\u662f\u5426\u6709\u5339\u914d\u7684\u884c\u3002\u9019\u5728\u9700\u8981\u7372\u53d6\u6240\u6709\u6578\u64da\u7684\u60c5\u6cc1\u4e0b\u975e\u5e38\u6709\u7528\u3002<\/p>\n
SELECT a.employee_id, a.first_name, b.department_name\nFROM employees a\nFULL OUTER JOIN departments b ON a.department_id = b.department_id;<\/code><\/pre>\n
\u9019\u500b\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u54e1\u5de5\u548c\u6240\u6709\u90e8\u9580\u7684\u6578\u64da\uff0c\u7121\u8ad6\u5b83\u5011\u662f\u5426\u6709\u5339\u914d\u7684\u95dc\u4fc2\u3002<\/p>\n
5. \u4ea4\u53c9Join (CROSS JOIN)<\/h2>\n
\u4ea4\u53c9Join\u8fd4\u56de\u5169\u500b\u8868\u7684\u7b1b\u5361\u723e\u7a4d\uff0c\u5373\u6bcf\u500b\u5de6\u8868\u7684\u884c\u90fd\u8207\u53f3\u8868\u7684\u6bcf\u4e00\u884c\u76f8\u7d50\u5408\u3002\u9019\u7a2eJoin\u901a\u5e38\u4e0d\u5e38\u7528\uff0c\u56e0\u70ba\u5b83\u6703\u751f\u6210\u5927\u91cf\u7684\u6578\u64da\u3002<\/p>\n
SELECT a.employee_id, b.department_name\nFROM employees a\nCROSS JOIN departments b;<\/code><\/pre>\n
\u9019\u500b\u67e5\u8a62\u5c07\u8fd4\u56de\u6bcf\u4f4d\u54e1\u5de5\u8207\u6bcf\u500b\u90e8\u9580\u7684\u7d44\u5408\uff0c\u751f\u6210\u7684\u7d50\u679c\u96c6\u53ef\u80fd\u975e\u5e38\u9f90\u5927\u3002<\/p>\n
\u7e3d\u7d50<\/h2>\n
Oracle\u7684Join\u64cd\u4f5c\u662f\u6578\u64da\u67e5\u8a62\u4e2d\u4e0d\u53ef\u6216\u7f3a\u7684\u4e00\u90e8\u5206\uff0c\u80fd\u5920\u5e6b\u52a9\u7528\u6236\u5f9e\u591a\u500b\u8868\u4e2d\u63d0\u53d6\u6240\u9700\u7684\u4fe1\u606f\u3002\u7121\u8ad6\u662f\u5167\u90e8Join\u3001\u5916\u90e8Join\u9084\u662f\u4ea4\u53c9Join\uff0c\u6839\u64da\u5177\u9ad4\u9700\u6c42\u9078\u64c7\u5408\u9069\u7684Join\u985e\u578b\u662f\u975e\u5e38\u91cd\u8981\u7684\u3002\u5c0d\u65bc\u9700\u8981\u9ad8\u6548\u6578\u64da\u8655\u7406\u7684\u4f01\u696d\uff0c\u9078\u64c7\u5408\u9069\u7684\u6578\u64da\u5eab\u548c\u670d\u52d9\u5668\u74b0\u5883\u81f3\u95dc\u91cd\u8981\u3002\u4e86\u89e3\u5982\u4f55\u5728Oracle\u4e2d\u4f7f\u7528Join\u64cd\u4f5c\uff0c\u53ef\u4ee5\u5e6b\u52a9\u958b\u767c\u8005\u66f4\u597d\u5730\u8a2d\u8a08\u548c\u512a\u5316\u6578\u64da\u5eab\u67e5\u8a62\u3002<\/p>\n
\u5982\u679c\u60a8\u5c0d\u65bc\u6578\u64da\u5eab\u7ba1\u7406\u6216\u5176\u4ed6\u6280\u8853\u89e3\u6c7a\u65b9\u6848\u6709\u8208\u8da3\uff0c\u6b61\u8fce\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u4e86\u89e3\u66f4\u591a\u4fe1\u606f\uff0c\u63a2\u7d22\u6211\u5011\u7684VPS<\/a>\u3001\u9999\u6e2f\u4f3a\u670d\u5668<\/a>\u53ca\u5176\u4ed6\u670d\u52d9\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u63a2\u7d22Oracle join\u7684\u5be6\u969b\u61c9\u7528\u4ee3\u78bc\uff0c\u4e86\u89e3\u5982\u4f55\u6709\u6548\u6574\u5408\u6578\u64da\uff0c\u63d0\u5347\u67e5\u8a62\u6548\u7387\u8207\u6578\u64da\u5206\u6790\u80fd\u529b\u3002<\/p>\n","protected":false},"author":0,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-93952","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/93952","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=93952"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/93952\/revisions"}],"predecessor-version":[{"id":93953,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/93952\/revisions\/93953"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=93952"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=93952"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=93952"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}