{"id":153063,"date":"2024-11-02T04:19:18","date_gmt":"2024-11-01T20:19:18","guid":{"rendered":"https:\/\/server.hk\/cnblog\/153063\/"},"modified":"2024-11-02T04:19:18","modified_gmt":"2024-11-01T20:19:18","slug":"%e5%89%b5%e5%bb%ba-oracle-%e7%b4%a2%e5%bc%95%e7%9a%84%e6%96%b9%e6%b3%95","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/153063\/","title":{"rendered":"\u5275\u5efa Oracle \u7d22\u5f15\u7684\u65b9\u6cd5"},"content":{"rendered":"<h1 id=\"%e5%89%b5%e5%bb%ba-oracle-%e7%b4%a2%e5%bc%95%e7%9a%84%e6%96%b9%e6%b3%95-RsQJOoqvIG\">\u5275\u5efa Oracle \u7d22\u5f15\u7684\u65b9\u6cd5<\/h1>\n<p>\u5728\u8cc7\u6599\u5eab\u7ba1\u7406\u4e2d\uff0c\u7d22\u5f15\u662f\u4e00\u7a2e\u91cd\u8981\u7684\u7d50\u69cb\uff0c\u80fd\u5920\u986f\u8457\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\u3002Oracle \u8cc7\u6599\u5eab\u63d0\u4f9b\u4e86\u591a\u7a2e\u7d22\u5f15\u985e\u578b\u548c\u5275\u5efa\u65b9\u6cd5\uff0c\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0e\u5982\u4f55\u5728 Oracle \u4e2d\u5275\u5efa\u7d22\u5f15\uff0c\u4e26\u63d0\u4f9b\u76f8\u95dc\u7684\u7bc4\u4f8b\u548c\u6700\u4f73\u5be6\u8e10\u3002<\/p>\n<h2 id=\"%e4%bb%80%e9%ba%bc%e6%98%af%e7%b4%a2%e5%bc%95%ef%bc%9f-RsQJOoqvIG\">\u4ec0\u9ebc\u662f\u7d22\u5f15\uff1f<\/h2>\n<p>\u7d22\u5f15\u662f\u4e00\u7a2e\u8cc7\u6599\u7d50\u69cb\uff0c\u80fd\u5920\u52a0\u901f\u8cc7\u6599\u5eab\u67e5\u8a62\u7684\u901f\u5ea6\u3002\u5b83\u985e\u4f3c\u65bc\u66f8\u7c4d\u7684\u76ee\u9304\uff0c\u5e6b\u52a9\u8cc7\u6599\u5eab\u5feb\u901f\u5b9a\u4f4d\u5230\u6240\u9700\u7684\u8cc7\u6599\u3002\u7d22\u5f15\u53ef\u4ee5\u5728\u4e00\u500b\u6216\u591a\u500b\u5217\u4e0a\u5275\u5efa\uff0c\u4e26\u4e14\u53ef\u4ee5\u7528\u65bc\u63d0\u9ad8 SELECT \u67e5\u8a62\u7684\u6548\u7387\u3002<\/p>\n<h2 id=\"oracle-%e4%b8%ad%e7%9a%84%e7%b4%a2%e5%bc%95%e9%a1%9e%e5%9e%8b-RsQJOoqvIG\">Oracle \u4e2d\u7684\u7d22\u5f15\u985e\u578b<\/h2>\n<p>Oracle \u652f\u63f4\u591a\u7a2e\u7d22\u5f15\u985e\u578b\uff0c\u4e3b\u8981\u5305\u62ec\uff1a<\/p>\n<ul>\n<li><strong>B\u6a39\u7d22\u5f15\uff08B-tree Index\uff09<\/strong>\uff1a\u6700\u5e38\u7528\u7684\u7d22\u5f15\u985e\u578b\uff0c\u9069\u7528\u65bc\u5927\u591a\u6578\u67e5\u8a62\u3002<\/li>\n<li><strong>\u4f4d\u5716\u7d22\u5f15\uff08Bitmap Index\uff09<\/strong>\uff1a\u9069\u5408\u65bc\u4f4e\u57fa\u6578\u7684\u5217\uff0c\u80fd\u5920\u6709\u6548\u5730\u8655\u7406\u5927\u91cf\u7684\u8cc7\u6599\u3002<\/li>\n<li><strong>\u552f\u4e00\u7d22\u5f15\uff08Unique Index\uff09<\/strong>\uff1a\u78ba\u4fdd\u7d22\u5f15\u5217\u7684\u503c\u552f\u4e00\uff0c\u901a\u5e38\u7528\u65bc\u4e3b\u9375\u3002<\/li>\n<li><strong>\u53cd\u5411\u7d22\u5f15\uff08Reverse Key Index\uff09<\/strong>\uff1a\u7528\u65bc\u9632\u6b62\u7d22\u5f15\u7684\u71b1\u9ede\u554f\u984c\uff0c\u7279\u5225\u662f\u5728\u63d2\u5165\u64cd\u4f5c\u983b\u7e41\u7684\u60c5\u6cc1\u4e0b\u3002<\/li>\n<li><strong>\u51fd\u6578\u7d22\u5f15\uff08Function-based Index\uff09<\/strong>\uff1a\u57fa\u65bc\u8868\u4e2d\u67d0\u500b\u5217\u7684\u8a08\u7b97\u7d50\u679c\u5275\u5efa\u7684\u7d22\u5f15\u3002<\/li>\n<\/ul>\n<h2 id=\"%e5%89%b5%e5%bb%ba%e7%b4%a2%e5%bc%95%e7%9a%84%e5%9f%ba%e6%9c%ac%e8%aa%9e%e6%b3%95-RsQJOoqvIG\">\u5275\u5efa\u7d22\u5f15\u7684\u57fa\u672c\u8a9e\u6cd5<\/h2>\n<p>\u5728 Oracle \u4e2d\uff0c\u5275\u5efa\u7d22\u5f15\u7684\u57fa\u672c\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>CREATE INDEX index_name\nON table_name (column1, column2, ...);\n<\/code><\/pre>\n<p>\u5176\u4e2d\uff0c<code>index_name<\/code> \u662f\u7d22\u5f15\u7684\u540d\u7a31\uff0c<code>table_name<\/code> \u662f\u8981\u5275\u5efa\u7d22\u5f15\u7684\u8868\u540d\uff0c<code>column1, column2, ...<\/code> \u662f\u8981\u7d22\u5f15\u7684\u5217\u3002<\/p>\n<h2 id=\"%e7%af%84%e4%be%8b%ef%bc%9a%e5%89%b5%e5%bb%ba%e4%b8%80%e5%80%8b-b-%e6%a8%b9%e7%b4%a2%e5%bc%95-RsQJOoqvIG\">\u7bc4\u4f8b\uff1a\u5275\u5efa\u4e00\u500b B \u6a39\u7d22\u5f15<\/h2>\n<p>\u5047\u8a2d\u6211\u5011\u6709\u4e00\u500b\u540d\u70ba <code>employees<\/code> \u7684\u8868\uff0c\u4e26\u5e0c\u671b\u5728 <code>last_name<\/code> \u5217\u4e0a\u5275\u5efa\u4e00\u500b\u7d22\u5f15\uff0c\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>CREATE INDEX idx_last_name\nON employees (last_name);\n<\/code><\/pre>\n<p>\u9019\u6a23\u5c31\u6703\u5728 <code>last_name<\/code> \u5217\u4e0a\u5275\u5efa\u4e00\u500b\u540d\u70ba <code>idx_last_name<\/code> \u7684 B \u6a39\u7d22\u5f15\u3002<\/p>\n<h2 id=\"%e5%89%b5%e5%bb%ba%e5%94%af%e4%b8%80%e7%b4%a2%e5%bc%95%e7%9a%84%e7%af%84%e4%be%8b-RsQJOoqvIG\">\u5275\u5efa\u552f\u4e00\u7d22\u5f15\u7684\u7bc4\u4f8b<\/h2>\n<p>\u5982\u679c\u6211\u5011\u5e0c\u671b\u78ba\u4fdd <code>email<\/code> \u5217\u7684\u552f\u4e00\u6027\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u8a9e\u6cd5\u5275\u5efa\u552f\u4e00\u7d22\u5f15\uff1a<\/p>\n<pre><code>CREATE UNIQUE INDEX idx_unique_email\nON employees (email);\n<\/code><\/pre>\n<h2 id=\"%e4%bd%bf%e7%94%a8%e5%87%bd%e6%95%b8%e7%b4%a2%e5%bc%95%e7%9a%84%e7%af%84%e4%be%8b-RsQJOoqvIG\">\u4f7f\u7528\u51fd\u6578\u7d22\u5f15\u7684\u7bc4\u4f8b<\/h2>\n<p>\u5982\u679c\u6211\u5011\u5e0c\u671b\u5728 <code>employees<\/code> \u8868\u7684 <code>hire_date<\/code> \u5217\u4e0a\u5275\u5efa\u4e00\u500b\u57fa\u65bc\u51fd\u6578\u7684\u7d22\u5f15\uff0c\u4ee5\u4fbf\u5feb\u901f\u67e5\u8a62\u67d0\u500b\u5e74\u4efd\u7684\u54e1\u5de5\uff0c\u53ef\u4ee5\u9019\u6a23\u505a\uff1a<\/p>\n<pre><code>CREATE INDEX idx_hire_year\nON employees (EXTRACT(YEAR FROM hire_date));\n<\/code><\/pre>\n<h2 id=\"%e7%b4%a2%e5%bc%95%e7%9a%84%e7%ae%a1%e7%90%86-RsQJOoqvIG\">\u7d22\u5f15\u7684\u7ba1\u7406<\/h2>\n<p>\u5275\u5efa\u7d22\u5f15\u5f8c\uff0c\u9084\u9700\u8981\u5b9a\u671f\u9032\u884c\u7ba1\u7406\u548c\u7dad\u8b77\u3002\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\u4f86\u67e5\u770b\u8cc7\u6599\u5eab\u4e2d\u7684\u6240\u6709\u7d22\u5f15\uff1a<\/p>\n<pre><code>SELECT index_name, table_name\nFROM user_indexes;\n<\/code><\/pre>\n<p>\u6b64\u5916\uff0c\u7576\u8cc7\u6599\u8868\u7684\u8cc7\u6599\u767c\u751f\u8b8a\u5316\u6642\uff0c\u7d22\u5f15\u4e5f\u9700\u8981\u9032\u884c\u66f4\u65b0\u3002\u9019\u53ef\u80fd\u6703\u5f71\u97ff\u63d2\u5165\u3001\u66f4\u65b0\u548c\u522a\u9664\u64cd\u4f5c\u7684\u6027\u80fd\uff0c\u56e0\u6b64\u5728\u8a2d\u8a08\u8cc7\u6599\u5eab\u6642\u9700\u8981\u8b39\u614e\u8003\u616e\u7d22\u5f15\u7684\u4f7f\u7528\u3002<\/p>\n<h2 id=\"%e7%b8%bd%e7%b5%90-RsQJOoqvIG\">\u7e3d\u7d50<\/h2>\n<p>\u5728 Oracle \u4e2d\u5275\u5efa\u7d22\u5f15\u662f\u4e00\u500b\u91cd\u8981\u7684\u6b65\u9a5f\uff0c\u53ef\u4ee5\u986f\u8457\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\u3002\u4e86\u89e3\u4e0d\u540c\u985e\u578b\u7684\u7d22\u5f15\u53ca\u5176\u4f7f\u7528\u60c5\u5883\uff0c\u80fd\u5920\u5e6b\u52a9\u8cc7\u6599\u5eab\u7ba1\u7406\u54e1\u66f4\u6709\u6548\u5730\u8a2d\u8a08\u548c\u512a\u5316\u8cc7\u6599\u5eab\u7d50\u69cb\u3002\u5c0d\u65bc\u9700\u8981\u9ad8\u6548\u80fd\u7684\u61c9\u7528\uff0c\u9078\u64c7\u5408\u9069\u7684\u7d22\u5f15\u985e\u578b\u548c\u5275\u5efa\u65b9\u6cd5\u81f3\u95dc\u91cd\u8981\u3002<\/p>\n<p>\u5982\u9700\u9032\u4e00\u6b65\u4e86\u89e3\u6709\u95dc <a href=\"https:\/\/server.hk\">\u9999\u6e2f VPS<\/a> \u548c\u5176\u4ed6\u4f3a\u670d\u5668\u89e3\u6c7a\u65b9\u6848\u7684\u4fe1\u606f\uff0c\u8acb\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3\u5982\u4f55\u5728 Oracle \u4e2d\u5275\u5efa\u7d22\u5f15\uff0c\u63d0\u5347\u67e5\u8a62\u6027\u80fd\uff0c\u512a\u5316\u6578\u64da\u5eab\u6548\u7387\uff0c\u7c21\u5316\u6578\u64da\u6aa2\u7d22\u904e\u7a0b\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-153063","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/153063","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=153063"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/153063\/revisions"}],"predecessor-version":[{"id":153064,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/153063\/revisions\/153064"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=153063"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=153063"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=153063"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}