{"id":94280,"date":"2024-10-19T18:59:17","date_gmt":"2024-10-19T10:59:17","guid":{"rendered":"https:\/\/server.hk\/cnblog\/94280\/"},"modified":"2024-10-19T18:59:17","modified_gmt":"2024-10-19T10:59:17","slug":"oracle-sql-%e6%80%a7%e8%83%bd%e5%a6%82%e4%bd%95%e9%80%b2%e8%a1%8c%e8%aa%bf%e6%95%b4","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/94280\/","title":{"rendered":"Oracle sql \u6027\u80fd\u5982\u4f55\u9032\u884c\u8abf\u6574"},"content":{"rendered":"<h1 id=\"oracle-sql-%e6%80%a7%e8%83%bd%e5%a6%82%e4%bd%95%e9%80%b2%e8%a1%8c%e8%aa%bf%e6%95%b4-gXjQLqJLlO\">Oracle SQL \u6027\u80fd\u5982\u4f55\u9032\u884c\u8abf\u6574<\/h1>\n<p>\u5728\u7576\u4eca\u6578\u64da\u9a45\u52d5\u7684\u4e16\u754c\u4e2d\uff0c\u6578\u64da\u5eab\u7684\u6027\u80fd\u5c0d\u65bc\u4f01\u696d\u7684\u904b\u71df\u81f3\u95dc\u91cd\u8981\u3002Oracle SQL \u4f5c\u70ba\u4e00\u7a2e\u5f37\u5927\u7684\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\uff0c\u63d0\u4f9b\u4e86\u591a\u7a2e\u5de5\u5177\u548c\u6280\u8853\u4f86\u512a\u5316\u67e5\u8a62\u6027\u80fd\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u5982\u4f55\u6709\u6548\u5730\u8abf\u6574 Oracle SQL \u7684\u6027\u80fd\uff0c\u4ee5\u63d0\u9ad8\u6578\u64da\u8655\u7406\u7684\u6548\u7387\u3002<\/p>\n<h2 id=\"1-%e7%90%86%e8%a7%a3%e5%9f%b7%e8%a1%8c%e8%a8%88%e5%8a%83-gXjQLqJLlO\">1. \u7406\u89e3\u57f7\u884c\u8a08\u5283<\/h2>\n<p>\u57f7\u884c\u8a08\u5283\u662f Oracle SQL \u5728\u57f7\u884c\u67e5\u8a62\u6642\u6240\u63a1\u7528\u7684\u6b65\u9a5f\u3002\u901a\u904e\u5206\u6790\u57f7\u884c\u8a08\u5283\uff0c\u958b\u767c\u8005\u53ef\u4ee5\u4e86\u89e3\u67e5\u8a62\u7684\u6027\u80fd\u74f6\u9838\u3002\u4f7f\u7528\u4ee5\u4e0b SQL \u8a9e\u53e5\u53ef\u4ee5\u67e5\u770b\u57f7\u884c\u8a08\u5283\uff1a<\/p>\n<pre><code>EXPLAIN PLAN FOR \nSELECT * FROM employees WHERE department_id = 10;<\/code><\/pre>\n<p>\u57f7\u884c\u8a08\u5283\u7684\u7d50\u679c\u53ef\u4ee5\u5e6b\u52a9\u8b58\u5225\u662f\u5426\u4f7f\u7528\u4e86\u7d22\u5f15\u3001\u5168\u8868\u6383\u63cf\u7b49\u64cd\u4f5c\uff0c\u5f9e\u800c\u9032\u4e00\u6b65\u8abf\u6574\u67e5\u8a62\u3002<\/p>\n<h2 id=\"2-%e4%bd%bf%e7%94%a8%e7%b4%a2%e5%bc%95-gXjQLqJLlO\">2. \u4f7f\u7528\u7d22\u5f15<\/h2>\n<p>\u7d22\u5f15\u662f\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\u7684\u95dc\u9375\u3002\u9069\u7576\u7684\u7d22\u5f15\u53ef\u4ee5\u986f\u8457\u6e1b\u5c11\u67e5\u8a62\u7684\u57f7\u884c\u6642\u9593\u3002\u4ee5\u4e0b\u662f\u4e00\u4e9b\u5e38\u898b\u7684\u7d22\u5f15\u985e\u578b\uff1a<\/p>\n<ul>\n<li><strong>B-tree \u7d22\u5f15\uff1a<\/strong>\u9069\u7528\u65bc\u7bc4\u570d\u67e5\u8a62\u3002<\/li>\n<li><strong>\u4f4d\u5716\u7d22\u5f15\uff1a<\/strong>\u9069\u5408\u65bc\u4f4e\u57fa\u6578\u7684\u5217\u3002<\/li>\n<li><strong>\u51fd\u6578\u7d22\u5f15\uff1a<\/strong>\u5c0d\u65bc\u8a08\u7b97\u7d50\u679c\u9032\u884c\u7d22\u5f15\u3002<\/li>\n<\/ul>\n<p>\u4f8b\u5982\uff0c\u5c0d\u65bc\u7d93\u5e38\u67e5\u8a62\u7684\u5217\uff0c\u53ef\u4ee5\u5275\u5efa B-tree \u7d22\u5f15\uff1a<\/p>\n<pre><code>CREATE INDEX idx_department ON employees(department_id);<\/code><\/pre>\n<h2 id=\"3-%e5%84%aa%e5%8c%96-sql-%e6%9f%a5%e8%a9%a2-gXjQLqJLlO\">3. \u512a\u5316 SQL \u67e5\u8a62<\/h2>\n<p>\u64b0\u5beb\u9ad8\u6548\u7684 SQL \u67e5\u8a62\u662f\u6027\u80fd\u8abf\u6574\u7684\u91cd\u8981\u4e00\u74b0\u3002\u4ee5\u4e0b\u662f\u4e00\u4e9b\u512a\u5316\u5efa\u8b70\uff1a<\/p>\n<ul>\n<li>\u907f\u514d\u4f7f\u7528 SELECT *\uff0c\u53ea\u9078\u64c7\u9700\u8981\u7684\u5217\u3002<\/li>\n<li>\u4f7f\u7528 JOIN \u800c\u975e\u5b50\u67e5\u8a62\uff0c\u56e0\u70ba JOIN \u901a\u5e38\u66f4\u9ad8\u6548\u3002<\/li>\n<li>\u4f7f\u7528 WHERE \u5b50\u53e5\u904e\u6ffe\u4e0d\u5fc5\u8981\u7684\u6578\u64da\u3002<\/li>\n<\/ul>\n<p>\u4f8b\u5982\uff0c\u4ee5\u4e0b\u67e5\u8a62\u53ef\u4ee5\u9032\u884c\u512a\u5316\uff1a<\/p>\n<pre><code>SELECT first_name, last_name \nFROM employees \nWHERE department_id = 10;<\/code><\/pre>\n<h2 id=\"4-%e8%aa%bf%e6%95%b4%e6%95%b8%e6%93%9a%e5%ba%ab%e5%8f%83%e6%95%b8-gXjQLqJLlO\">4. \u8abf\u6574\u6578\u64da\u5eab\u53c3\u6578<\/h2>\n<p>Oracle \u63d0\u4f9b\u4e86\u591a\u7a2e\u53c3\u6578\u4f86\u8abf\u6574\u6578\u64da\u5eab\u6027\u80fd\u3002\u4ee5\u4e0b\u662f\u4e00\u4e9b\u91cd\u8981\u7684\u53c3\u6578\uff1a<\/p>\n<ul>\n<li><strong>SGA (System Global Area)\uff1a<\/strong>\u8abf\u6574 SGA \u7684\u5927\u5c0f\u53ef\u4ee5\u63d0\u9ad8\u6578\u64da\u7de9\u5b58\u7684\u6548\u7387\u3002<\/li>\n<li><strong>PGA (Program Global Area)\uff1a<\/strong>\u589e\u52a0 PGA \u7684\u5927\u5c0f\u53ef\u4ee5\u63d0\u9ad8\u6392\u5e8f\u548c\u54c8\u5e0c\u64cd\u4f5c\u7684\u6027\u80fd\u3002<\/li>\n<\/ul>\n<p>\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\u67e5\u770b\u7576\u524d\u7684 SGA \u548c PGA \u8a2d\u7f6e\uff1a<\/p>\n<pre><code>SHOW PARAMETER sga_target;\nSHOW PARAMETER pga_aggregate_target;<\/code><\/pre>\n<h2 id=\"5-%e5%ae%9a%e6%9c%9f%e7%b6%ad%e8%ad%b7%e6%95%b8%e6%93%9a%e5%ba%ab-gXjQLqJLlO\">5. \u5b9a\u671f\u7dad\u8b77\u6578\u64da\u5eab<\/h2>\n<p>\u5b9a\u671f\u7684\u6578\u64da\u5eab\u7dad\u8b77\u53ef\u4ee5\u9632\u6b62\u6027\u80fd\u4e0b\u964d\u3002\u4ee5\u4e0b\u662f\u4e00\u4e9b\u7dad\u8b77\u5efa\u8b70\uff1a<\/p>\n<ul>\n<li>\u5b9a\u671f\u91cd\u5efa\u7d22\u5f15\uff0c\u4ee5\u9632\u6b62\u788e\u7247\u5316\u3002<\/li>\n<li>\u66f4\u65b0\u7d71\u8a08\u4fe1\u606f\uff0c\u4ee5\u5e6b\u52a9 Oracle \u66f4\u597d\u5730\u9078\u64c7\u57f7\u884c\u8a08\u5283\u3002<\/li>\n<li>\u6e05\u7406\u4e0d\u5fc5\u8981\u7684\u6578\u64da\uff0c\u6e1b\u5c11\u6578\u64da\u5eab\u7684\u5927\u5c0f\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-gXjQLqJLlO\">\u7e3d\u7d50<\/h2>\n<p>\u8abf\u6574 Oracle SQL \u6027\u80fd\u662f\u4e00\u500b\u6301\u7e8c\u7684\u904e\u7a0b\uff0c\u6d89\u53ca\u5230\u57f7\u884c\u8a08\u5283\u5206\u6790\u3001\u7d22\u5f15\u4f7f\u7528\u3001\u67e5\u8a62\u512a\u5316\u3001\u6578\u64da\u5eab\u53c3\u6578\u8abf\u6574\u548c\u5b9a\u671f\u7dad\u8b77\u7b49\u591a\u500b\u65b9\u9762\u3002\u901a\u904e\u9019\u4e9b\u65b9\u6cd5\uff0c\u4f01\u696d\u53ef\u4ee5\u986f\u8457\u63d0\u9ad8\u6578\u64da\u8655\u7406\u7684\u6548\u7387\uff0c\u5f9e\u800c\u66f4\u597d\u5730\u652f\u6301\u696d\u52d9\u9700\u6c42\u3002\u5982\u679c\u60a8\u9700\u8981\u9032\u4e00\u6b65\u7684\u652f\u6301\u6216\u89e3\u6c7a\u65b9\u6848\uff0c\u8acb\u8003\u616e\u6211\u5011\u7684 <a href=\"https:\/\/server.hk\">\u9999\u6e2f VPS<\/a> \u670d\u52d9\uff0c\u70ba\u60a8\u7684\u6578\u64da\u5eab\u63d0\u4f9b\u7a69\u5b9a\u7684\u904b\u884c\u74b0\u5883\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3\u5982\u4f55\u8abf\u6574Oracle SQL\u6027\u80fd\uff0c\u63d0\u5347\u67e5\u8a62\u6548\u7387\uff0c\u512a\u5316\u6578\u64da\u5eab\u904b\u884c\uff0c\u5be6\u73fe\u66f4\u5feb\u7684\u6578\u64da\u8655\u7406\u548c\u97ff\u61c9\u6642\u9593\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-94280","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/94280","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=94280"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/94280\/revisions"}],"predecessor-version":[{"id":94281,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/94280\/revisions\/94281"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=94280"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=94280"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=94280"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}