{"id":94602,"date":"2024-10-19T19:37:17","date_gmt":"2024-10-19T11:37:17","guid":{"rendered":"https:\/\/server.hk\/cnblog\/94602\/"},"modified":"2024-10-19T19:37:18","modified_gmt":"2024-10-19T11:37:18","slug":"oracle-%e5%9f%ba%e7%a4%8e%e7%9f%a5%e8%ad%98%e4%b8%ad%e5%be%9e%e5%a4%9a%e5%80%8b%e8%a1%a8%e9%87%8c%e9%81%b8%e5%8f%96%e6%95%b8%e6%93%9a%e8%a8%98%e9%8c%84%e7%9a%84%e6%96%b9%e6%b3%95","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/94602\/","title":{"rendered":"Oracle \u57fa\u790e\u77e5\u8b58\u4e2d\u5f9e\u591a\u500b\u8868\u91cc\u9078\u53d6\u6578\u64da\u8a18\u9304\u7684\u65b9\u6cd5"},"content":{"rendered":"

Oracle \u57fa\u790e\u77e5\u8b58\u4e2d\u5f9e\u591a\u500b\u8868\u91cc\u9078\u53d6\u6578\u64da\u8a18\u9304\u7684\u65b9\u6cd5<\/h1>\n

\u5728\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0cOracle \u662f\u4e00\u500b\u5ee3\u6cdb\u4f7f\u7528\u7684\u95dc\u4fc2\u578b\u6578\u64da\u5eab\u3002\u7576\u6211\u5011\u9700\u8981\u5f9e\u591a\u500b\u8868\u4e2d\u9078\u53d6\u6578\u64da\u8a18\u9304\u6642\uff0c\u4e86\u89e3\u5982\u4f55\u6709\u6548\u5730\u4f7f\u7528 SQL \u8a9e\u53e5\u662f\u81f3\u95dc\u91cd\u8981\u7684\u3002\u672c\u6587\u5c07\u4ecb\u7d39\u5e7e\u7a2e\u5f9e\u591a\u500b\u8868\u4e2d\u9078\u53d6\u6578\u64da\u7684\u65b9\u6cd5\uff0c\u5305\u62ec\u806f\u63a5\uff08JOIN\uff09\u3001\u5b50\u67e5\u8a62\uff08SUBQUERY\uff09\u548c\u96c6\u5408\u64cd\u4f5c\uff08SET OPERATIONS\uff09\u3002<\/p>\n

1. \u806f\u63a5\uff08JOIN\uff09<\/h2>\n

\u806f\u63a5\u662f\u5f9e\u591a\u500b\u8868\u4e2d\u9078\u53d6\u6578\u64da\u7684\u6700\u5e38\u7528\u65b9\u6cd5\u4e4b\u4e00\u3002Oracle \u652f\u6301\u591a\u7a2e\u806f\u63a5\u985e\u578b\uff0c\u5305\u62ec\u5167\u90e8\u806f\u63a5\uff08INNER JOIN\uff09\u3001\u5916\u90e8\u806f\u63a5\uff08OUTER JOIN\uff09\u548c\u4ea4\u53c9\u806f\u63a5\uff08CROSS JOIN\uff09\u3002<\/p>\n

1.1 \u5167\u90e8\u806f\u63a5\uff08INNER JOIN\uff09<\/h3>\n

\u5167\u90e8\u806f\u63a5\u53ea\u8fd4\u56de\u5728\u5169\u500b\u8868\u4e2d\u90fd\u6709\u7684\u8a18\u9304\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u793a\u4f8b\uff0c\u5047\u8a2d\u6211\u5011\u6709\u5169\u500b\u8868\uff1aemployees<\/code> \u548c departments<\/code>\u3002<\/p>\n

SELECT e.employee_id, e.first_name, d.department_name\nFROM employees e\nINNER JOIN departments d ON e.department_id = d.department_id;<\/code><\/pre>\n
\u9019\u6bb5 SQL \u8a9e\u53e5\u5c07\u8fd4\u56de\u6240\u6709\u54e1\u5de5\u53ca\u5176\u6240\u5c6c\u90e8\u9580\u7684\u540d\u7a31\u3002<\/p>\n
1.2 \u5916\u90e8\u806f\u63a5\uff08OUTER JOIN\uff09<\/h3>\n
\u5916\u90e8\u806f\u63a5\u53ef\u4ee5\u8fd4\u56de\u4e00\u500b\u8868\u4e2d\u7684\u6240\u6709\u8a18\u9304\uff0c\u5373\u4f7f\u5728\u53e6\u4e00\u500b\u8868\u4e2d\u6c92\u6709\u5339\u914d\u7684\u8a18\u9304\u3002\u5916\u90e8\u806f\u63a5\u5206\u70ba\u5de6\u5916\u90e8\u806f\u63a5\uff08LEFT OUTER JOIN\uff09\u548c\u53f3\u5916\u90e8\u806f\u63a5\uff08RIGHT OUTER JOIN\uff09\u3002\u4ee5\u4e0b\u662f\u5de6\u5916\u90e8\u806f\u63a5\u7684\u793a\u4f8b\uff1a<\/p>\n
SELECT e.employee_id, e.first_name, d.department_name\nFROM employees e\nLEFT OUTER JOIN departments d ON e.department_id = d.department_id;<\/code><\/pre>\n
\u9019\u6bb5 SQL \u8a9e\u53e5\u5c07\u8fd4\u56de\u6240\u6709\u54e1\u5de5\u7684\u8a18\u9304\uff0c\u5373\u4f7f\u67d0\u4e9b\u54e1\u5de5\u6c92\u6709\u6240\u5c6c\u90e8\u9580\u3002<\/p>\n
1.3 \u4ea4\u53c9\u806f\u63a5\uff08CROSS JOIN\uff09<\/h3>\n
\u4ea4\u53c9\u806f\u63a5\u8fd4\u56de\u5169\u500b\u8868\u7684\u7b1b\u5361\u723e\u7a4d\uff0c\u5373\u6bcf\u500b\u8868\u4e2d\u7684\u6bcf\u4e00\u884c\u90fd\u8207\u53e6\u4e00\u500b\u8868\u4e2d\u7684\u6bcf\u4e00\u884c\u76f8\u7d50\u5408\u3002\u4ee5\u4e0b\u662f\u4ea4\u53c9\u806f\u63a5\u7684\u793a\u4f8b\uff1a<\/p>\n
SELECT e.first_name, d.department_name\nFROM employees e\nCROSS JOIN departments d;<\/code><\/pre>\n
\u9019\u6bb5 SQL \u8a9e\u53e5\u5c07\u8fd4\u56de\u6240\u6709\u54e1\u5de5\u8207\u6240\u6709\u90e8\u9580\u7684\u7d44\u5408\u3002<\/p>\n
2. \u5b50\u67e5\u8a62\uff08SUBQUERY\uff09<\/h2>\n
\u5b50\u67e5\u8a62\u662f\u5d4c\u5957\u5728\u5176\u4ed6\u67e5\u8a62\u4e2d\u7684\u67e5\u8a62\u3002\u5b83\u53ef\u4ee5\u7528\u65bc\u5f9e\u4e00\u500b\u8868\u4e2d\u9078\u53d6\u6578\u64da\uff0c\u7136\u5f8c\u5728\u53e6\u4e00\u500b\u67e5\u8a62\u4e2d\u4f7f\u7528\u9019\u4e9b\u6578\u64da\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u793a\u4f8b\uff1a<\/p>\n
SELECT employee_id, first_name\nFROM employees\nWHERE department_id IN (SELECT department_id FROM departments WHERE location_id = 1000);<\/code><\/pre>\n
\u9019\u6bb5 SQL \u8a9e\u53e5\u5c07\u8fd4\u56de\u6240\u6709\u5728\u7279\u5b9a\u5730\u9ede\u5de5\u4f5c\u7684\u54e1\u5de5\u3002<\/p>\n
3. \u96c6\u5408\u64cd\u4f5c\uff08SET OPERATIONS\uff09<\/h2>\n
\u96c6\u5408\u64cd\u4f5c\u5141\u8a31\u6211\u5011\u5c07\u591a\u500b\u67e5\u8a62\u7684\u7d50\u679c\u5408\u4f75\u5728\u4e00\u8d77\u3002Oracle \u652f\u6301\u7684\u96c6\u5408\u64cd\u4f5c\u5305\u62ec UNION\u3001INTERSECT \u548c MINUS\u3002\u4ee5\u4e0b\u662f\u4f7f\u7528 UNION \u7684\u793a\u4f8b\uff1a<\/p>\n
SELECT first_name FROM employees\nUNION\nSELECT department_name FROM departments;<\/code><\/pre>\n
\u9019\u6bb5 SQL \u8a9e\u53e5\u5c07\u8fd4\u56de\u54e1\u5de5\u7684\u540d\u5b57\u548c\u90e8\u9580\u7684\u540d\u7a31\uff0c\u4e26\u53bb\u9664\u91cd\u8907\u7684\u8a18\u9304\u3002<\/p>\n
\u7e3d\u7d50<\/h2>\n
\u5728 Oracle \u6578\u64da\u5eab\u4e2d\uff0c\u5f9e\u591a\u500b\u8868\u4e2d\u9078\u53d6\u6578\u64da\u8a18\u9304\u7684\u65b9\u6cd5\u6709\u5f88\u591a\uff0c\u5305\u62ec\u806f\u63a5\u3001\u5b50\u67e5\u8a62\u548c\u96c6\u5408\u64cd\u4f5c\u3002\u9019\u4e9b\u6280\u8853\u4e0d\u50c5\u80fd\u63d0\u9ad8\u67e5\u8a62\u7684\u9748\u6d3b\u6027\uff0c\u9084\u80fd\u5e6b\u52a9\u7528\u6236\u66f4\u6709\u6548\u5730\u7ba1\u7406\u548c\u5206\u6790\u6578\u64da\u3002\u5c0d\u65bc\u9700\u8981\u9ad8\u6548\u6578\u64da\u8655\u7406\u7684\u4f01\u696d\u4f86\u8aaa\uff0c\u9078\u64c7\u5408\u9069\u7684\u6578\u64da\u5eab\u89e3\u6c7a\u65b9\u6848\u81f3\u95dc\u91cd\u8981\u3002\u82e5\u60a8\u5c0d\u65bc \u9999\u6e2f VPS<\/a> \u6216\u5176\u4ed6 \u4f3a\u670d\u5668<\/a> \u89e3\u6c7a\u65b9\u6848\u611f\u8208\u8da3\uff0c\u8acb\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u4ee5\u7372\u53d6\u66f4\u591a\u4fe1\u606f\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u4e86\u89e3Oracle\u57fa\u790e\u77e5\u8b58\uff0c\u5b78\u7fd2\u5982\u4f55\u5f9e\u591a\u500b\u8868\u4e2d\u9078\u53d6\u6578\u64da\u8a18\u9304\u7684\u65b9\u6cd5\uff0c\u63d0\u5347\u6578\u64da\u67e5\u8a62\u6548\u7387\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-94602","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/94602","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=94602"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/94602\/revisions"}],"predecessor-version":[{"id":94603,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/94602\/revisions\/94603"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=94602"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=94602"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=94602"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}