{"id":95226,"date":"2024-10-19T23:17:15","date_gmt":"2024-10-19T15:17:15","guid":{"rendered":"https:\/\/server.hk\/cnblog\/95226\/"},"modified":"2024-10-19T23:17:16","modified_gmt":"2024-10-19T15:17:16","slug":"oracle%e9%80%b2%e8%a1%8c%e6%95%b8%e6%93%9a%e5%ba%ab%e6%9f%a5%e8%a9%a2%e7%9a%84%e5%b0%8f%e6%8a%80%e5%b7%a7","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/95226\/","title":{"rendered":"Oracle\u9032\u884c\u6578\u64da\u5eab\u67e5\u8a62\u7684\u5c0f\u6280\u5de7"},"content":{"rendered":"<h1 id=\"oracle%e9%80%b2%e8%a1%8c%e6%95%b8%e6%93%9a%e5%ba%ab%e6%9f%a5%e8%a9%a2%e7%9a%84%e5%b0%8f%e6%8a%80%e5%b7%a7-ofybycuiNO\">Oracle\u9032\u884c\u6578\u64da\u5eab\u67e5\u8a62\u7684\u5c0f\u6280\u5de7<\/h1>\n<p>\u5728\u7576\u4eca\u6578\u64da\u9a45\u52d5\u7684\u4e16\u754c\u4e2d\uff0c\u6578\u64da\u5eab\u67e5\u8a62\u7684\u6548\u7387\u548c\u6e96\u78ba\u6027\u5c0d\u65bc\u4f01\u696d\u7684\u6210\u529f\u81f3\u95dc\u91cd\u8981\u3002Oracle\u6578\u64da\u5eab\u4f5c\u70ba\u4e00\u500b\u5f37\u5927\u7684\u6578\u64da\u7ba1\u7406\u7cfb\u7d71\uff0c\u63d0\u4f9b\u4e86\u591a\u7a2e\u67e5\u8a62\u529f\u80fd\u548c\u512a\u5316\u6280\u5de7\u3002\u672c\u6587\u5c07\u4ecb\u7d39\u4e00\u4e9b\u5728Oracle\u4e2d\u9032\u884c\u6578\u64da\u5eab\u67e5\u8a62\u7684\u5c0f\u6280\u5de7\uff0c\u5e6b\u52a9\u7528\u6236\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\u548c\u6548\u7387\u3002<\/p>\n<h2 id=\"1-%e4%bd%bf%e7%94%a8%e7%b4%a2%e5%bc%95%e4%be%86%e5%8a%a0%e9%80%9f%e6%9f%a5%e8%a9%a2-ofybycuiNO\">1. \u4f7f\u7528\u7d22\u5f15\u4f86\u52a0\u901f\u67e5\u8a62<\/h2>\n<p>\u7d22\u5f15\u662f\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\u7684\u95dc\u9375\u3002\u901a\u904e\u5728\u8868\u7684\u67d0\u4e9b\u5217\u4e0a\u5275\u5efa\u7d22\u5f15\uff0c\u53ef\u4ee5\u986f\u8457\u6e1b\u5c11\u67e5\u8a62\u6240\u9700\u7684\u6642\u9593\u3002\u4ee5\u4e0b\u662f\u5275\u5efa\u7d22\u5f15\u7684\u57fa\u672c\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>CREATE INDEX index_name ON table_name (column_name);<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u5982\u679c\u6211\u5011\u6709\u4e00\u500b\u540d\u70ba\u201cemployees\u201d\u7684\u8868\uff0c\u4e26\u4e14\u7d93\u5e38\u6839\u64da\u201clast_name\u201d\u9032\u884c\u67e5\u8a62\uff0c\u53ef\u4ee5\u9019\u6a23\u5275\u5efa\u7d22\u5f15\uff1a<\/p>\n<pre><code>CREATE INDEX idx_last_name ON employees (last_name);<\/code><\/pre>\n<h2 id=\"2-%e4%bd%bf%e7%94%a8explain-plan%e5%88%86%e6%9e%90%e6%9f%a5%e8%a9%a2-ofybycuiNO\">2. \u4f7f\u7528EXPLAIN PLAN\u5206\u6790\u67e5\u8a62<\/h2>\n<p>\u5728\u57f7\u884c\u67e5\u8a62\u4e4b\u524d\uff0c\u4f7f\u7528EXPLAIN PLAN\u53ef\u4ee5\u5e6b\u52a9\u7528\u6236\u4e86\u89e3Oracle\u5982\u4f55\u57f7\u884c\u8a72\u67e5\u8a62\u3002\u9019\u5c0d\u65bc\u8b58\u5225\u6f5b\u5728\u7684\u6027\u80fd\u74f6\u9838\u975e\u5e38\u6709\u7528\u3002\u4f7f\u7528\u65b9\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>EXPLAIN PLAN FOR\nSELECT * FROM employees WHERE last_name = 'Smith';<\/code><\/pre>\n<p>\u57f7\u884c\u5f8c\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u67e5\u8a62\u67e5\u770b\u57f7\u884c\u8a08\u5283\uff1a<\/p>\n<pre><code>SELECT * FROM TABLE(DBMS_XPLAN.DISPLAY);<\/code><\/pre>\n<h2 id=\"3-%e9%81%bf%e5%85%8dselect-ofybycuiNO\">3. \u907f\u514dSELECT *<\/h2>\n<p>\u5728\u67e5\u8a62\u4e2d\u4f7f\u7528\u201cSELECT *\u201d\u6703\u5c0e\u81f4\u4e0d\u5fc5\u8981\u7684\u6578\u64da\u50b3\u8f38\uff0c\u5f9e\u800c\u5f71\u97ff\u6027\u80fd\u3002\u61c9\u8a72\u660e\u78ba\u6307\u5b9a\u6240\u9700\u7684\u5217\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT first_name, last_name FROM employees;<\/code><\/pre>\n<h2 id=\"4-%e4%bd%bf%e7%94%a8where%e5%ad%90%e5%8f%a5%e9%81%8e%e6%bf%be%e6%95%b8%e6%93%9a-ofybycuiNO\">4. \u4f7f\u7528WHERE\u5b50\u53e5\u904e\u6ffe\u6578\u64da<\/h2>\n<p>\u5728\u67e5\u8a62\u4e2d\u4f7f\u7528WHERE\u5b50\u53e5\u53ef\u4ee5\u6709\u6548\u5730\u904e\u6ffe\u6578\u64da\uff0c\u6e1b\u5c11\u8fd4\u56de\u7684\u884c\u6578\u3002\u9019\u4e0d\u50c5\u63d0\u9ad8\u4e86\u67e5\u8a62\u901f\u5ea6\uff0c\u9084\u6e1b\u5c11\u4e86\u7cfb\u7d71\u8cc7\u6e90\u7684\u6d88\u8017\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT * FROM employees WHERE department_id = 10;<\/code><\/pre>\n<h2 id=\"5-%e4%bd%bf%e7%94%a8join%e8%80%8c%e9%9d%9e%e5%ad%90%e6%9f%a5%e8%a9%a2-ofybycuiNO\">5. \u4f7f\u7528JOIN\u800c\u975e\u5b50\u67e5\u8a62<\/h2>\n<p>\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\uff0c\u4f7f\u7528JOIN\u64cd\u4f5c\u6bd4\u4f7f\u7528\u5b50\u67e5\u8a62\u66f4\u6709\u6548\u3002JOIN\u53ef\u4ee5\u5728\u55ae\u500b\u67e5\u8a62\u4e2d\u7372\u53d6\u591a\u500b\u8868\u7684\u6578\u64da\uff0c\u5f9e\u800c\u63d0\u9ad8\u6027\u80fd\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT e.first_name, d.department_name\nFROM employees e\nJOIN departments d ON e.department_id = d.department_id;<\/code><\/pre>\n<h2 id=\"6-%e4%bd%bf%e7%94%a8%e8%81%9a%e5%90%88%e5%87%bd%e6%95%b8-ofybycuiNO\">6. \u4f7f\u7528\u805a\u5408\u51fd\u6578<\/h2>\n<p>\u5728\u9700\u8981\u8a08\u7b97\u7e3d\u548c\u3001\u5e73\u5747\u503c\u6216\u5176\u4ed6\u7d71\u8a08\u6578\u64da\u6642\uff0c\u4f7f\u7528\u805a\u5408\u51fd\u6578\u53ef\u4ee5\u7c21\u5316\u67e5\u8a62\u4e26\u63d0\u9ad8\u6548\u7387\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT department_id, COUNT(*) AS employee_count\nFROM employees\nGROUP BY department_id;<\/code><\/pre>\n<h2 id=\"7-%e5%ae%9a%e6%9c%9f%e7%b6%ad%e8%ad%b7%e6%95%b8%e6%93%9a%e5%ba%ab-ofybycuiNO\">7. \u5b9a\u671f\u7dad\u8b77\u6578\u64da\u5eab<\/h2>\n<p>\u5b9a\u671f\u9032\u884c\u6578\u64da\u5eab\u7dad\u8b77\uff0c\u5982\u91cd\u5efa\u7d22\u5f15\u548c\u66f4\u65b0\u7d71\u8a08\u4fe1\u606f\uff0c\u53ef\u4ee5\u4fdd\u6301\u67e5\u8a62\u6027\u80fd\u7684\u7a69\u5b9a\u3002\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\u66f4\u65b0\u7d71\u8a08\u4fe1\u606f\uff1a<\/p>\n<pre><code>EXEC DBMS_STATS.GATHER_TABLE_STATS('schema_name', 'table_name');<\/code><\/pre>\n<h2 id=\"%e7%b8%bd%e7%b5%90-ofybycuiNO\">\u7e3d\u7d50<\/h2>\n<p>\u638c\u63e1Oracle\u6578\u64da\u5eab\u67e5\u8a62\u7684\u5c0f\u6280\u5de7\u53ef\u4ee5\u986f\u8457\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\u548c\u6548\u7387\u3002\u901a\u904e\u4f7f\u7528\u7d22\u5f15\u3001\u5206\u6790\u67e5\u8a62\u8a08\u5283\u3001\u907f\u514d\u4e0d\u5fc5\u8981\u7684\u6578\u64da\u50b3\u8f38\u4ee5\u53ca\u9032\u884c\u5b9a\u671f\u7dad\u8b77\uff0c\u4f7f\u7528\u8005\u53ef\u4ee5\u66f4\u6709\u6548\u5730\u7ba1\u7406\u6578\u64da\u5eab\u3002\u5c0d\u65bc\u9700\u8981\u9ad8\u6548\u6578\u64da\u8655\u7406\u7684\u4f01\u696d\uff0c\u9078\u64c7\u5408\u9069\u7684 <a href=\"https:\/\/server.hk\">VPS<\/a> \u89e3\u6c7a\u65b9\u6848\u4e5f\u662f\u81f3\u95dc\u91cd\u8981\u7684\u3002\u4e86\u89e3\u66f4\u591a\u95dc\u65bc <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u548c <a href=\"https:\/\/server.hk\">\u96f2\u4f3a\u670d\u5668<\/a> \u7684\u4fe1\u606f\uff0c\u8acb\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u638c\u63e1Oracle\u6578\u64da\u5eab\u67e5\u8a62\u7684\u5c0f\u6280\u5de7\uff0c\u63d0\u5347\u67e5\u8a62\u6548\u7387\uff0c\u512a\u5316\u6027\u80fd\uff0c\u8b93\u6578\u64da\u7ba1\u7406\u66f4\u8f15\u9b06\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-95226","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/95226","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=95226"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/95226\/revisions"}],"predecessor-version":[{"id":95227,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/95226\/revisions\/95227"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=95226"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=95226"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=95226"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}