{"id":60653,"date":"2024-10-13T04:40:17","date_gmt":"2024-10-12T20:40:17","guid":{"rendered":"https:\/\/server.hk\/cnblog\/60653\/"},"modified":"2024-10-13T04:40:17","modified_gmt":"2024-10-12T20:40:17","slug":"db2%e6%95%b8%e6%93%9a%e5%ba%absql%e7%b7%a8%e7%a2%bc%e5%84%aa%e5%8c%96%e8%88%87%e6%80%a7%e8%83%bd%e6%8f%8f%e8%bf%b0","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/60653\/","title":{"rendered":"DB2\u6578\u64da\u5eabSQL\u7de8\u78bc\u512a\u5316\u8207\u6027\u80fd\u63cf\u8ff0"},"content":{"rendered":"<h1 id=\"db2%e6%95%b8%e6%93%9a%e5%ba%absql%e7%b7%a8%e7%a2%bc%e5%84%aa%e5%8c%96%e8%88%87%e6%80%a7%e8%83%bd%e6%8f%8f%e8%bf%b0-SMzqppjUyy\">DB2\u6578\u64da\u5eabSQL\u7de8\u78bc\u512a\u5316\u8207\u6027\u80fd\u63cf\u8ff0<\/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\u6210\u529f\u81f3\u95dc\u91cd\u8981\u3002IBM\u7684DB2\u6578\u64da\u5eab\u662f\u4e00\u500b\u5f37\u5927\u7684\u95dc\u4fc2\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\uff0c\u5ee3\u6cdb\u61c9\u7528\u65bc\u5404\u7a2e\u884c\u696d\u3002\u70ba\u4e86\u78ba\u4fddDB2\u6578\u64da\u5eab\u7684\u9ad8\u6548\u904b\u884c\uff0cSQL\u7de8\u78bc\u7684\u512a\u5316\u662f\u4e0d\u53ef\u6216\u7f3a\u7684\u4e00\u74b0\u3002\u672c\u6587\u5c07\u63a2\u8a0eDB2\u6578\u64da\u5eab\u7684SQL\u7de8\u78bc\u512a\u5316\u6280\u8853\u53ca\u5176\u5c0d\u6027\u80fd\u7684\u5f71\u97ff\u3002<\/p>\n<h2 id=\"sql%e7%b7%a8%e7%a2%bc%e5%84%aa%e5%8c%96%e7%9a%84%e5%9f%ba%e6%9c%ac%e5%8e%9f%e5%89%87-SMzqppjUyy\">SQL\u7de8\u78bc\u512a\u5316\u7684\u57fa\u672c\u539f\u5247<\/h2>\n<p>\u5728\u9032\u884cSQL\u7de8\u78bc\u512a\u5316\u6642\uff0c\u6709\u5e7e\u500b\u57fa\u672c\u539f\u5247\u9700\u8981\u9075\u5faa\uff1a<\/p>\n<ul>\n<li><strong>\u907f\u514d\u4e0d\u5fc5\u8981\u7684\u8a08\u7b97\uff1a<\/strong>\u5728\u67e5\u8a62\u4e2d\uff0c\u61c9\u76e1\u91cf\u907f\u514d\u5728WHERE\u5b50\u53e5\u4e2d\u9032\u884c\u8a08\u7b97\uff0c\u56e0\u70ba\u9019\u6703\u5c0e\u81f4\u5168\u8868\u6383\u63cf\u3002\u4f8b\u5982\uff0c\u5c07\u4ee5\u4e0b\u67e5\u8a62\uff1a<\/li>\n<\/ul>\n<pre><code>SELECT * FROM employees WHERE YEAR(hire_date) = 2020;<\/code><\/pre>\n<ul>\n<li>\u512a\u5316\u70ba\uff1a<\/li>\n<\/ul>\n<pre><code>SELECT * FROM employees WHERE hire_date BETWEEN '2020-01-01' AND '2020-12-31';<\/code><\/pre>\n<ul>\n<li><strong>\u4f7f\u7528\u7d22\u5f15\uff1a<\/strong>\u7d22\u5f15\u53ef\u4ee5\u986f\u8457\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\u3002\u78ba\u4fdd\u5728\u7d93\u5e38\u7528\u65bc\u67e5\u8a62\u7684\u5217\u4e0a\u5275\u5efa\u7d22\u5f15\uff0c\u7279\u5225\u662f\u4e3b\u9375\u548c\u5916\u9375\u3002<\/li>\n<li><strong>\u9078\u64c7\u5408\u9069\u7684\u6578\u64da\u985e\u578b\uff1a<\/strong>\u4f7f\u7528\u5408\u9069\u7684\u6578\u64da\u985e\u578b\u53ef\u4ee5\u6e1b\u5c11\u5b58\u5132\u7a7a\u9593\u4e26\u63d0\u9ad8\u6027\u80fd\u3002\u4f8b\u5982\uff0c\u5c0d\u65bc\u5c0f\u7bc4\u570d\u7684\u6574\u6578\uff0c\u4f7f\u7528TINYINT\u800c\u4e0d\u662fINT\u3002<\/li>\n<li><strong>\u907f\u514dSELECT *\uff1a<\/strong>\u5728\u67e5\u8a62\u4e2d\u907f\u514d\u4f7f\u7528SELECT *\uff0c\u61c9\u660e\u78ba\u6307\u5b9a\u6240\u9700\u7684\u5217\uff0c\u9019\u6a23\u53ef\u4ee5\u6e1b\u5c11\u6578\u64da\u50b3\u8f38\u91cf\u3002<\/li>\n<\/ul>\n<h2 id=\"%e6%9f%a5%e8%a9%a2%e6%80%a7%e8%83%bd%e5%88%86%e6%9e%90-SMzqppjUyy\">\u67e5\u8a62\u6027\u80fd\u5206\u6790<\/h2>\n<p>DB2\u63d0\u4f9b\u4e86\u591a\u7a2e\u5de5\u5177\u4f86\u5206\u6790\u67e5\u8a62\u6027\u80fd\u3002\u4f7f\u7528EXPLAIN\u547d\u4ee4\u53ef\u4ee5\u7372\u53d6\u67e5\u8a62\u7684\u57f7\u884c\u8a08\u5283\uff0c\u5e6b\u52a9\u958b\u767c\u8005\u4e86\u89e3\u67e5\u8a62\u7684\u57f7\u884c\u65b9\u5f0f\u3002<\/p>\n<pre><code>EXPLAIN PLAN FOR SELECT * FROM employees WHERE department_id = 10;<\/code><\/pre>\n<p>\u57f7\u884c\u6b64\u547d\u4ee4\u5f8c\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u67e5\u8a62\u4f86\u67e5\u770b\u57f7\u884c\u8a08\u5283\uff1a<\/p>\n<pre><code>SELECT * FROM EXPLAIN_STATEMENT;<\/code><\/pre>\n<p>\u901a\u904e\u5206\u6790\u57f7\u884c\u8a08\u5283\uff0c\u958b\u767c\u8005\u53ef\u4ee5\u8b58\u5225\u6027\u80fd\u74f6\u9838\uff0c\u4e26\u6839\u64da\u9700\u8981\u9032\u884c\u512a\u5316\u3002<\/p>\n<h2 id=\"%e4%bd%bf%e7%94%a8%e5%ad%98%e5%84%b2%e9%81%8e%e7%a8%8b%e5%92%8c%e8%a7%b8%e7%99%bc%e5%99%a8-SMzqppjUyy\">\u4f7f\u7528\u5b58\u5132\u904e\u7a0b\u548c\u89f8\u767c\u5668<\/h2>\n<p>\u5b58\u5132\u904e\u7a0b\u548c\u89f8\u767c\u5668\u662fDB2\u4e2d\u63d0\u9ad8\u6027\u80fd\u7684\u53e6\u4e00\u7a2e\u6709\u6548\u65b9\u6cd5\u3002\u5b58\u5132\u904e\u7a0b\u53ef\u4ee5\u5c07\u591a\u500bSQL\u8a9e\u53e5\u5c01\u88dd\u5728\u4e00\u8d77\uff0c\u6e1b\u5c11\u7db2\u7d61\u50b3\u8f38\u7684\u958b\u92b7\u3002\u89f8\u767c\u5668\u5247\u53ef\u4ee5\u81ea\u52d5\u57f7\u884c\u67d0\u4e9b\u64cd\u4f5c\uff0c\u5f9e\u800c\u6e1b\u5c11\u61c9\u7528\u7a0b\u5e8f\u7684\u8ca0\u64d4\u3002<\/p>\n<pre><code>CREATE PROCEDURE update_employee_salary(IN emp_id INT, IN new_salary DECIMAL(10,2))\nBEGIN\n    UPDATE employees SET salary = new_salary WHERE id = emp_id;\nEND;<\/code><\/pre>\n<p>\u9019\u6a23\u7684\u5b58\u5132\u904e\u7a0b\u53ef\u4ee5\u5728\u9700\u8981\u66f4\u65b0\u54e1\u5de5\u85aa\u8cc7\u6642\u88ab\u8abf\u7528\uff0c\u5f9e\u800c\u63d0\u9ad8\u6548\u7387\u3002<\/p>\n<h2 id=\"%e6%80%a7%e8%83%bd%e6%b8%ac%e8%a9%a6%e8%88%87%e7%9b%a3%e6%8e%a7-SMzqppjUyy\">\u6027\u80fd\u6e2c\u8a66\u8207\u76e3\u63a7<\/h2>\n<p>\u5728\u9032\u884cSQL\u7de8\u78bc\u512a\u5316\u5f8c\uff0c\u6301\u7e8c\u7684\u6027\u80fd\u6e2c\u8a66\u8207\u76e3\u63a7\u662f\u5fc5\u4e0d\u53ef\u5c11\u7684\u3002DB2\u63d0\u4f9b\u4e86\u591a\u7a2e\u6027\u80fd\u76e3\u63a7\u5de5\u5177\uff0c\u5982DB2 Performance Expert\uff0c\u53ef\u4ee5\u5e6b\u52a9\u7528\u6236\u5be6\u6642\u76e3\u63a7\u6578\u64da\u5eab\u6027\u80fd\uff0c\u53ca\u6642\u767c\u73fe\u554f\u984c\u4e26\u9032\u884c\u8abf\u6574\u3002<\/p>\n<h2 id=\"%e7%b8%bd%e7%b5%90-SMzqppjUyy\">\u7e3d\u7d50<\/h2>\n<p>DB2\u6578\u64da\u5eab\u7684SQL\u7de8\u78bc\u512a\u5316\u662f\u63d0\u9ad8\u6578\u64da\u5eab\u6027\u80fd\u7684\u95dc\u9375\u3002\u901a\u904e\u9075\u5faa\u57fa\u672c\u539f\u5247\u3001\u5206\u6790\u67e5\u8a62\u6027\u80fd\u3001\u4f7f\u7528\u5b58\u5132\u904e\u7a0b\u548c\u89f8\u767c\u5668\uff0c\u4ee5\u53ca\u6301\u7e8c\u7684\u6027\u80fd\u6e2c\u8a66\u8207\u76e3\u63a7\uff0c\u4f01\u696d\u53ef\u4ee5\u986f\u8457\u63d0\u5347\u5176\u6578\u64da\u5eab\u7684\u904b\u884c\u6548\u7387\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\uff0c\u5982<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u6216<a href=\"https:\/\/server.hk\">\u9999\u6e2f\u4f3a\u670d\u5668<\/a>\uff0c\u5c07\u6709\u52a9\u65bc\u5be6\u73fe\u66f4\u597d\u7684\u6027\u80fd\u548c\u7a69\u5b9a\u6027\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u63a2\u7d22DB2\u6578\u64da\u5eab\u7684SQL\u7de8\u78bc\u512a\u5316\u6280\u5de7\uff0c\u63d0\u5347\u6027\u80fd\uff0c\u78ba\u4fdd\u9ad8\u6548\u6578\u64da\u8655\u7406\u8207\u67e5\u8a62\u901f\u5ea6\u3002<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-60653","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/60653","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"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=60653"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/60653\/revisions"}],"predecessor-version":[{"id":60654,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/60653\/revisions\/60654"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=60653"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=60653"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=60653"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}