{"id":95314,"date":"2024-10-20T00:01:18","date_gmt":"2024-10-19T16:01:18","guid":{"rendered":"https:\/\/server.hk\/cnblog\/95314\/"},"modified":"2024-10-20T00:01:18","modified_gmt":"2024-10-19T16:01:18","slug":"oracle%e8%aa%8d%e8%ad%89%ef%bc%9aoracle%e5%84%aa%e5%8c%96%e5%99%a8%e7%9a%84%e5%84%aa%e5%8c%96%e6%96%b9%e5%bc%8f","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/95314\/","title":{"rendered":"Oracle\u8a8d\u8b49\uff1aOracle\u512a\u5316\u5668\u7684\u512a\u5316\u65b9\u5f0f"},"content":{"rendered":"<h1 id=\"oracle%e8%aa%8d%e8%ad%89%ef%bc%9aoracle%e5%84%aa%e5%8c%96%e5%99%a8%e7%9a%84%e5%84%aa%e5%8c%96%e6%96%b9%e5%bc%8f-AcBuWsncJb\">Oracle\u8a8d\u8b49\uff1aOracle\u512a\u5316\u5668\u7684\u512a\u5316\u65b9\u5f0f<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0cOracle\u512a\u5316\u5668\u662f\u78ba\u4fdd\u67e5\u8a62\u6027\u80fd\u7684\u95dc\u9375\u7d44\u4ef6\u3002\u5b83\u7684\u4e3b\u8981\u529f\u80fd\u662f\u5206\u6790SQL\u67e5\u8a62\u4e26\u751f\u6210\u6700\u4f73\u7684\u57f7\u884c\u8a08\u5283\uff0c\u4ee5\u63d0\u9ad8\u6578\u64da\u6aa2\u7d22\u7684\u6548\u7387\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0eOracle\u512a\u5316\u5668\u7684\u5de5\u4f5c\u539f\u7406\u53ca\u5176\u512a\u5316\u65b9\u5f0f\uff0c\u5e6b\u52a9\u8b80\u8005\u66f4\u597d\u5730\u7406\u89e3\u5982\u4f55\u5229\u7528\u9019\u4e00\u5de5\u5177\u4f86\u63d0\u5347\u6578\u64da\u5eab\u6027\u80fd\u3002<\/p>\n<h2 id=\"oracle%e5%84%aa%e5%8c%96%e5%99%a8%e7%9a%84%e5%9f%ba%e6%9c%ac%e6%a6%82%e5%bf%b5-AcBuWsncJb\">Oracle\u512a\u5316\u5668\u7684\u57fa\u672c\u6982\u5ff5<\/h2>\n<p>Oracle\u512a\u5316\u5668\u662f\u4e00\u500b\u81ea\u52d5\u5316\u7684\u7cfb\u7d71\uff0c\u8ca0\u8cac\u6c7a\u5b9a\u5982\u4f55\u57f7\u884cSQL\u67e5\u8a62\u3002\u5b83\u6839\u64da\u591a\u7a2e\u56e0\u7d20\u4f86\u8a55\u4f30\u4e0d\u540c\u7684\u57f7\u884c\u8a08\u5283\uff0c\u5305\u62ec\u6578\u64da\u5206\u4f48\u3001\u7d22\u5f15\u7684\u4f7f\u7528\u60c5\u6cc1\u3001\u8868\u7684\u5927\u5c0f\u7b49\u3002Oracle\u63d0\u4f9b\u4e86\u5169\u7a2e\u4e3b\u8981\u7684\u512a\u5316\u5668\uff1a\u6210\u672c\u512a\u5316\u5668\uff08Cost-Based Optimizer, CBO\uff09\u548c\u898f\u5247\u512a\u5316\u5668\uff08Rule-Based Optimizer, RBO\uff09\u3002\u76ee\u524d\uff0cCBO\u662fOracle\u7684\u9ed8\u8a8d\u9078\u64c7\uff0c\u56e0\u70ba\u5b83\u80fd\u5920\u6839\u64da\u5be6\u969b\u7684\u6578\u64da\u7d71\u8a08\u4fe1\u606f\u4f86\u751f\u6210\u66f4\u9ad8\u6548\u7684\u57f7\u884c\u8a08\u5283\u3002<\/p>\n<h2 id=\"%e5%84%aa%e5%8c%96%e5%99%a8%e7%9a%84%e5%b7%a5%e4%bd%9c%e6%b5%81%e7%a8%8b-AcBuWsncJb\">\u512a\u5316\u5668\u7684\u5de5\u4f5c\u6d41\u7a0b<\/h2>\n<p>Oracle\u512a\u5316\u5668\u7684\u5de5\u4f5c\u6d41\u7a0b\u53ef\u4ee5\u5206\u70ba\u4ee5\u4e0b\u5e7e\u500b\u6b65\u9a5f\uff1a<\/p>\n<ul>\n<li><strong>\u89e3\u6790\uff1a<\/strong>\u7576SQL\u67e5\u8a62\u88ab\u63d0\u4ea4\u6642\uff0c\u512a\u5316\u5668\u9996\u5148\u6703\u89e3\u6790\u67e5\u8a62\uff0c\u6aa2\u67e5\u8a9e\u6cd5\u548c\u8a9e\u7fa9\u7684\u6b63\u78ba\u6027\u3002<\/li>\n<li><strong>\u751f\u6210\u57f7\u884c\u8a08\u5283\uff1a<\/strong>\u512a\u5316\u5668\u6703\u6839\u64da\u67e5\u8a62\u7684\u7d50\u69cb\u548c\u6578\u64da\u5eab\u7684\u7d71\u8a08\u4fe1\u606f\u751f\u6210\u591a\u500b\u53ef\u80fd\u7684\u57f7\u884c\u8a08\u5283\u3002<\/li>\n<li><strong>\u8a55\u4f30\u8a08\u5283\uff1a<\/strong>\u6bcf\u500b\u57f7\u884c\u8a08\u5283\u90fd\u6703\u88ab\u8a55\u4f30\u5176\u6210\u672c\uff0c\u9019\u4e9b\u6210\u672c\u901a\u5e38\u57fa\u65bcI\/O\u64cd\u4f5c\u3001CPU\u4f7f\u7528\u7387\u7b49\u56e0\u7d20\u3002<\/li>\n<li><strong>\u9078\u64c7\u6700\u4f73\u8a08\u5283\uff1a<\/strong>\u6700\u7d42\uff0c\u512a\u5316\u5668\u6703\u9078\u64c7\u6210\u672c\u6700\u4f4e\u7684\u57f7\u884c\u8a08\u5283\u4f86\u57f7\u884c\u67e5\u8a62\u3002<\/li>\n<\/ul>\n<h2 id=\"%e5%84%aa%e5%8c%96%e5%99%a8%e7%9a%84%e5%84%aa%e5%8c%96%e6%96%b9%e5%bc%8f-AcBuWsncJb\">\u512a\u5316\u5668\u7684\u512a\u5316\u65b9\u5f0f<\/h2>\n<p>\u70ba\u4e86\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\uff0cOracle\u512a\u5316\u5668\u63d0\u4f9b\u4e86\u591a\u7a2e\u512a\u5316\u65b9\u5f0f\uff1a<\/p>\n<h3 id=\"1-%e4%bd%bf%e7%94%a8%e7%b4%a2%e5%bc%95-AcBuWsncJb\">1. \u4f7f\u7528\u7d22\u5f15<\/h3>\n<p>\u7d22\u5f15\u662f\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\u7684\u6709\u6548\u5de5\u5177\u3002\u512a\u5316\u5668\u6703\u6839\u64da\u67e5\u8a62\u7684\u689d\u4ef6\u81ea\u52d5\u9078\u64c7\u5408\u9069\u7684\u7d22\u5f15\u4f86\u52a0\u901f\u6578\u64da\u6aa2\u7d22\u3002\u4f8b\u5982\uff0c\u5c0d\u65bc\u4e00\u500b\u67e5\u8a62\uff1a<\/p>\n<pre><code>SELECT * FROM employees WHERE department_id = 10;<\/code><\/pre>\n<p>\u5982\u679c\u5728department_id\u5217\u4e0a\u6709\u7d22\u5f15\uff0c\u512a\u5316\u5668\u5c07\u6703\u4f7f\u7528\u8a72\u7d22\u5f15\u4f86\u52a0\u5feb\u67e5\u8a62\u901f\u5ea6\u3002<\/p>\n<h3 id=\"2-%e7%b5%b1%e8%a8%88%e4%bf%a1%e6%81%af%e7%9a%84%e6%94%b6%e9%9b%86-AcBuWsncJb\">2. \u7d71\u8a08\u4fe1\u606f\u7684\u6536\u96c6<\/h3>\n<p>\u512a\u5316\u5668\u4f9d\u8cf4\u65bc\u6e96\u78ba\u7684\u7d71\u8a08\u4fe1\u606f\u4f86\u751f\u6210\u6700\u4f73\u57f7\u884c\u8a08\u5283\u3002\u7528\u6236\u53ef\u4ee5\u4f7f\u7528DBMS_STATS\u5305\u4f86\u6536\u96c6\u548c\u66f4\u65b0\u7d71\u8a08\u4fe1\u606f\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>EXEC DBMS_STATS.GATHER_TABLE_STATS('HR', 'EMPLOYEES');<\/code><\/pre>\n<p>\u9019\u6a23\u53ef\u4ee5\u78ba\u4fdd\u512a\u5316\u5668\u64c1\u6709\u6700\u65b0\u7684\u6578\u64da\u5206\u4f48\u4fe1\u606f\uff0c\u5f9e\u800c\u505a\u51fa\u66f4\u597d\u7684\u6c7a\u7b56\u3002<\/p>\n<h3 id=\"3-%e6%9f%a5%e8%a9%a2%e9%87%8d%e5%af%ab-AcBuWsncJb\">3. \u67e5\u8a62\u91cd\u5beb<\/h3>\n<p>\u512a\u5316\u5668\u9084\u53ef\u4ee5\u901a\u904e\u67e5\u8a62\u91cd\u5beb\u4f86\u63d0\u9ad8\u6027\u80fd\u3002\u9019\u610f\u5473\u8457\u512a\u5316\u5668\u6703\u81ea\u52d5\u5c07\u8907\u96dc\u7684\u67e5\u8a62\u8f49\u63db\u70ba\u66f4\u7c21\u55ae\u7684\u5f62\u5f0f\uff0c\u4ee5\u6e1b\u5c11\u8a08\u7b97\u91cf\u3002\u4f8b\u5982\uff0c\u5c07\u591a\u500b\u806f\u63a5\u67e5\u8a62\u91cd\u5beb\u70ba\u5b50\u67e5\u8a62\uff0c\u5f9e\u800c\u63d0\u9ad8\u57f7\u884c\u6548\u7387\u3002<\/p>\n<h3 id=\"4-%e4%bd%bf%e7%94%a8%e6%8f%90%e7%a4%ba%ef%bc%88hints%ef%bc%89-AcBuWsncJb\">4. \u4f7f\u7528\u63d0\u793a\uff08Hints\uff09<\/h3>\n<p>\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\uff0c\u7528\u6236\u53ef\u80fd\u5e0c\u671b\u512a\u5316\u5668\u9075\u5faa\u7279\u5b9a\u7684\u57f7\u884c\u8a08\u5283\u3002\u9019\u6642\u53ef\u4ee5\u4f7f\u7528\u63d0\u793a\u4f86\u6307\u5c0e\u512a\u5316\u5668\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT \/*+ INDEX(employees emp_idx) *\/ * FROM employees WHERE department_id = 10;<\/code><\/pre>\n<p>\u9019\u6a23\u53ef\u4ee5\u5f37\u5236\u512a\u5316\u5668\u4f7f\u7528\u6307\u5b9a\u7684\u7d22\u5f15\u3002<\/p>\n<h2 id=\"%e7%b5%90%e8%ab%96-AcBuWsncJb\">\u7d50\u8ad6<\/h2>\n<p>Oracle\u512a\u5316\u5668\u662f\u63d0\u5347\u6578\u64da\u5eab\u67e5\u8a62\u6027\u80fd\u7684\u91cd\u8981\u5de5\u5177\u3002\u901a\u904e\u5408\u7406\u4f7f\u7528\u7d22\u5f15\u3001\u6536\u96c6\u7d71\u8a08\u4fe1\u606f\u3001\u67e5\u8a62\u91cd\u5beb\u548c\u63d0\u793a\u7b49\u65b9\u5f0f\uff0c\u4f7f\u7528\u8005\u53ef\u4ee5\u986f\u8457\u63d0\u9ad8\u67e5\u8a62\u7684\u57f7\u884c\u6548\u7387\u3002\u4e86\u89e3\u512a\u5316\u5668\u7684\u5de5\u4f5c\u539f\u7406\u548c\u512a\u5316\u65b9\u5f0f\uff0c\u5c07\u6709\u52a9\u65bc\u6578\u64da\u5eab\u7ba1\u7406\u8005\u66f4\u597d\u5730\u7ba1\u7406\u548c\u512a\u5316\u5176\u6578\u64da\u5eab\u7cfb\u7d71\u3002<\/p>\n<p>\u5982\u9700\u4e86\u89e3\u66f4\u591a\u6709\u95dc\u65bc<code><a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a><\/code>\u548c<code><a href=\"https:\/\/server.hk\">\u4e91\u670d\u52a1\u5668<\/a><\/code>\u7684\u8cc7\u8a0a\uff0c\u8acb\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3Oracle\u8a8d\u8b49\u4e2d\u7684\u512a\u5316\u5668\u512a\u5316\u65b9\u5f0f\uff0c\u63d0\u5347\u6578\u64da\u5eab\u6027\u80fd\uff0c\u638c\u63e1\u6700\u4f73\u5be6\u8e10\uff0c\u52a9\u529b\u5c08\u696d\u767c\u5c55\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-95314","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/95314","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=95314"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/95314\/revisions"}],"predecessor-version":[{"id":95315,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/95314\/revisions\/95315"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=95314"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=95314"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=95314"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}