{"id":5628,"date":"2024-11-14T08:18:30","date_gmt":"2024-11-14T00:18:30","guid":{"rendered":"https:\/\/fwq.ai\/blog\/5628\/"},"modified":"2024-11-14T08:18:30","modified_gmt":"2024-11-14T00:18:30","slug":"%e6%80%8e%e4%b9%88%e5%88%86%e6%9e%90sql%e7%9a%84%e6%89%a7%e8%a1%8c%e8%ae%a1%e5%88%92","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/5628\/","title":{"rendered":"\u600e\u4e48\u5206\u6790sql\u7684\u6267\u884c\u8ba1\u5212"},"content":{"rendered":"<blockquote><p>\n  \u5206\u6790 sql \u6267\u884c\u8ba1\u5212\u4ee5\u4f18\u5316\u67e5\u8be2\u6027\u80fd\uff1a\u83b7\u53d6\u6267\u884c\u8ba1\u5212\uff1a\u4f7f\u7528 sql \u8bed\u53e5\uff08\u5982 explain\uff09\u6765\u83b7\u53d6\u6267\u884c\u8ba1\u5212\u3002\u786e\u5b9a\u67e5\u8be2\u7c7b\u578b\uff1a\u8bc6\u522b\u67e5\u8be2\u7684\u7c7b\u578b\uff08\u5982 select\u3001insert\u3001update\u3001delete\uff09\u3002\u68c0\u67e5\u8868\u626b\u63cf\uff1a\u67e5\u627e\u5168\u8868\u626b\u63cf\uff08table scan\uff09\uff0c\u5e76\u68c0\u67e5\u662f\u5426\u9700\u8981\u521b\u5efa\u7d22\u5f15\u3002\u5206\u6790\u8fde\u63a5\uff1a\u786e\u5b9a\u8fde\u63a5\u7c7b\u578b\uff0c\u68c0\u67e5\u8fde\u63a5\u6761\u4ef6\uff0c\u5e76\u4f18\u5316\u8fde\u63a5\u987a\u5e8f\u3002\u8bc4\u4f30\u8868\u8fde\u63a5\u987a\u5e8f\uff1a\u68c0\u67e5\u8868\u8fde\u63a5\u7684\u987a\u5e8f\u662f\u5426\u6700\u4f18\u3002\u8bc6\u522b\u5217\u987a\u5e8f\uff1a\u786e\u4fdd\u8fde\u63a5\u7684\u5217\u987a\u5e8f\u4e0e\u9884\u671f\u7684\u4e00\u81f4\uff0c\u4ee5\u907f\u514d\u5168\u8868\u626b\u63cf\u3002\u67e5\u627e\u8ba1\u7b97\u6210\u672c\uff1a\u67e5\u770b\u6267\u884c\u8ba1\u5212\u4e2d\u7684\u884c\u6570\u4f30\u8ba1\uff08rows\uff09\uff0c\u8bc6\u522b\u9ad8\u8ba1\u7b97\u6210\u672c\u7684\n<\/p><\/blockquote>\n<p><img decoding=\"async\" src=\"https:\/\/img.php.cn\/upload\/article\/202405\/30\/2024053019184111413.jpg\" class=\"aligncenter\" title=\"\u600e\u4e48\u5206\u6790sql\u7684\u6267\u884c\u8ba1\u5212\u63d2\u56fe\" alt=\"\u600e\u4e48\u5206\u6790sql\u7684\u6267\u884c\u8ba1\u5212\u63d2\u56fe\" \/><\/p>\n<p><strong>\u5982\u4f55\u5206\u6790 SQL \u6267\u884c\u8ba1\u5212<\/strong><\/p>\n<p>\u6267\u884c\u8ba1\u5212\u662f\u6570\u636e\u5e93\u4f18\u5316\u5668\u751f\u6210\u7684\uff0c\u5b83\u63cf\u8ff0\u4e86\u6570\u636e\u5e93\u5c06\u5982\u4f55\u6267\u884c\u67e5\u8be2\u7684\u6b65\u9aa4\u3002\u5206\u6790\u6267\u884c\u8ba1\u5212\u5bf9\u4e8e\u8bc6\u522b\u67e5\u8be2\u6027\u80fd\u95ee\u9898\u548c\u5236\u5b9a\u4f18\u5316\u7b56\u7565\u81f3\u5173\u91cd\u8981\u3002<\/p>\n<p><strong>\u6b65\u9aa4 1\uff1a\u83b7\u53d6\u6267\u884c\u8ba1\u5212<\/strong><\/p>\n<p>\u6839\u636e\u4e0d\u540c\u7684\u6570\u636e\u5e93\u7cfb\u7edf\uff0c\u83b7\u53d6\u6267\u884c\u8ba1\u5212\u7684\u65b9\u6cd5\u4e0d\u540c\uff1a<\/p>\n<ul>\n<li> <strong>MySQL\uff1a<\/strong>\u4f7f\u7528 EXPLAIN  \u8bed\u53e5  <\/li>\n<li> <strong>PostgreSQL\uff1a<\/strong>\u4f7f\u7528 EXPLAIN (ANALYZE, BUFFERS) \u8bed\u53e5<\/li>\n<li> <strong>Oracle\uff1a<\/strong>\u4f7f\u7528 EXPLAIN PLAN FOR  \u8bed\u53e5  <\/li>\n<\/ul>\n<p><strong>\u6b65\u9aa4 2\uff1a\u786e\u5b9a\u67e5\u8be2\u7c7b\u578b<\/strong><\/p>\n<p>\u6267\u884c\u8ba1\u5212\u7684\u7b2c\u4e00\u884c\u63cf\u8ff0\u4e86\u67e5\u8be2\u7c7b\u578b\uff0c\u5982\uff1a<\/p>\n<ul>\n<li> <strong>SELECT<\/strong>\uff1a\u6570\u636e\u68c0\u7d22\u67e5\u8be2<\/li>\n<li> <strong>INSERT<\/strong>\uff1a\u6570\u636e\u63d2\u5165\u67e5\u8be2<\/li>\n<li> <strong>UPDATE<\/strong>\uff1a\u6570\u636e\u66f4\u65b0\u67e5\u8be2<\/li>\n<li> <strong>DELETE<\/strong>\uff1a\u6570\u636e\u5220\u9664\u67e5\u8be2<\/li>\n<\/ul>\n<p><strong>\u6b65\u9aa4 3\uff1a\u68c0\u67e5\u8868\u626b\u63cf<\/strong><\/p>\n<ul>\n<li>\u5bfb\u627e TABLE SCAN \u8868\u793a\u5168\u8868\u626b\u63cf\u3002\u8fd9\u53ef\u80fd\u8868\u660e\u9700\u8981\u521b\u5efa\u4e00\u4e2a\u7d22\u5f15\u6765\u4f18\u5316\u67e5\u8be2\u3002<\/li>\n<li>\u68c0\u67e5 EXTRA \u5217\u4e2d\u7684 Using index \u6307\u793a\u662f\u5426\u4f7f\u7528\u4e86\u7d22\u5f15\u3002<\/li>\n<\/ul>\n<p><strong>\u6b65\u9aa4 4\uff1a\u5206\u6790\u8fde\u63a5<\/strong><\/p>\n<ul>\n<li>\u786e\u5b9a\u8fde\u63a5\u7c7b\u578b\uff08\u5982\u5185\u90e8\u8fde\u63a5\u3001\u5916\u90e8\u8fde\u63a5\uff09\u3002<\/li>\n<li>\u68c0\u67e5\u8fde\u63a5\u6761\u4ef6\u4ee5\u786e\u4fdd\u5176\u6b63\u786e\u4e14\u9ad8\u6548\u3002<\/li>\n<li>\u4f7f\u7528 ON \u5173\u952e\u5b57\u800c\u4e0d\u662f WHERE \u5173\u952e\u5b57\u8fdb\u884c\u8fde\u63a5\u4ee5\u786e\u4fdd\u4f18\u5316\u5668\u6b63\u786e\u4f7f\u7528\u7d22\u5f15\u3002<\/li>\n<\/ul>\n<p><strong>\u6b65\u9aa4 5\uff1a\u8bc4\u4f30\u8868\u8fde\u63a5\u987a\u5e8f<\/strong><\/p>\n<p>\u67e5\u8be2\u6267\u884c\u7684\u987a\u5e8f\u5bf9\u6027\u80fd\u6709\u91cd\u5927\u5f71\u54cd\u3002\u67e5\u770b\u6267\u884c\u8ba1\u5212\u5e76\u786e\u5b9a\u8868\u8fde\u63a5\u7684\u987a\u5e8f\u662f\u5426\u6700\u4f73\u3002<\/p>\n<p><strong>\u6b65\u9aa4 6\uff1a\u8bc6\u522b\u5217\u987a\u5e8f<\/strong><\/p>\n<p>\u5728\u8fde\u63a5\u4e2d\uff0c\u8868\u7684\u987a\u5e8f\u51b3\u5b9a\u4e86\u8fde\u63a5\u4f7f\u7528\u7684\u5217\u3002\u786e\u4fdd\u5217\u987a\u5e8f\u4e0e\u9884\u671f\u7684\u4e00\u81f4\uff0c\u5426\u5219\u53ef\u80fd\u4f1a\u5bfc\u81f4\u4e0d\u5fc5\u8981\u7684\u5168\u8868\u626b\u63cf\u3002<\/p>\n<p><strong>\u6b65\u9aa4 7\uff1a\u67e5\u627e\u8ba1\u7b97\u6210\u672c<\/strong><\/p>\n<p>\u6267\u884c\u8ba1\u5212\u4e2d\u5305\u542b Rows \u5217\uff0c\u8868\u793a\u4f18\u5316\u5668\u4f30\u8ba1\u67e5\u8be2\u8fd4\u56de\u7684\u884c\u6570\u3002<\/p>\n<ul>\n<li>\u8f83\u9ad8\u7684 Rows \u503c\u8868\u660e\u67e5\u8be2\u9700\u8981\u5904\u7406\u5927\u91cf\u6570\u636e\uff0c\u9700\u8981\u4f18\u5316\u3002<\/li>\n<li>\u8f83\u4f4e\u7684 Rows \u503c\u8868\u660e\u67e5\u8be2\u76f8\u5bf9\u9ad8\u6548\u3002<\/li>\n<\/ul>\n<p><strong>\u6b65\u9aa4 8\uff1a\u8003\u8651\u7d22\u5f15\u8986\u76d6\u7d22\u5f15<\/strong><\/p>\n<ul>\n<li>\u68c0\u67e5 POSSIBLE_KEYS \u5217\u4ee5\u786e\u5b9a\u53ef\u80fd\u6709\u52a9\u4e8e\u67e5\u8be2\u7684\u7d22\u5f15\u3002<\/li>\n<li>\u5982\u679c KEY \u5217\u663e\u793a Using index_name\uff0c\u5219\u8868\u660e\u6b63\u5728\u4f7f\u7528\u7d22\u5f15\u8986\u76d6\u7d22\u5f15\uff0c\u65e0\u9700\u4ece\u8868\u4e2d\u8bfb\u53d6\u4efb\u4f55\u6570\u636e\u3002<\/li>\n<\/ul>\n<p>\u4ee5\u4e0a\u5c31\u662f\u600e\u4e48\u5206\u6790sql\u7684\u6267\u884c\u8ba1\u5212\u7684\u8be6\u7ec6\u5185\u5bb9\uff0c\u66f4\u591a\u8bf7\u5173\u6ce8\u7c73\u4e91\u7f51\u5176\u5b83\u76f8\u5173\u6587\u7ae0\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5206\u6790 sql \u6267\u884c\u8ba1\u5212\u4ee5\u4f18\u5316\u67e5\u8be2\u6027\u80fd\uff1a\u83b7\u53d6\u6267\u884c\u8ba1\u5212\uff1a\u4f7f\u7528 sql \u8bed\u53e5\uff08\u5982 explain\uff09\u6765\u83b7\u53d6\u6267\u884c\u8ba1\u5212\u3002\u786e\u5b9a\u67e5\u8be2\u7c7b\u578b\uff1a\u8bc6\u522b\u67e5\u8be2\u7684\u7c7b\u578b\uff08\u5982 select\u3001insert\u3001update\u3001delete\uff09\u3002\u68c0\u67e5\u8868\u626b\u63cf\uff1a\u67e5\u627e\u5168\u8868\u626b\u63cf\uff08table scan\uff09\uff0c\u5e76\u68c0\u67e5\u662f\u5426\u9700\u8981\u521b\u5efa\u7d22\u5f15\u3002\u5206\u6790\u8fde\u63a5\uff1a\u786e\u5b9a\u8fde\u63a5\u7c7b\u578b\uff0c\u68c0\u67e5\u8fde\u63a5\u6761\u4ef6\uff0c\u5e76\u4f18\u5316\u8fde\u63a5\u987a\u5e8f\u3002\u8bc4\u4f30\u8868\u8fde\u63a5\u987a\u5e8f\uff1a\u68c0\u67e5\u8868\u8fde\u63a5\u7684\u987a\u5e8f\u662f\u5426\u6700\u4f18\u3002\u8bc6\u522b\u5217\u987a\u5e8f\uff1a\u786e\u4fdd\u8fde\u63a5\u7684\u5217\u987a\u5e8f\u4e0e\u9884\u671f\u7684\u4e00\u81f4\uff0c\u4ee5\u907f\u514d\u5168\u8868\u626b\u63cf\u3002\u67e5\u627e\u8ba1\u7b97\u6210\u672c\uff1a\u67e5\u770b\u6267\u884c\u8ba1\u5212\u4e2d\u7684\u884c\u6570\u4f30\u8ba1\uff08rows\uff09\uff0c\u8bc6\u522b\u9ad8\u8ba1\u7b97\u6210\u672c\u7684 \u5982\u4f55\u5206\u6790 SQL \u6267\u884c\u8ba1\u5212 \u6267\u884c\u8ba1\u5212\u662f\u6570\u636e\u5e93\u4f18\u5316\u5668\u751f\u6210\u7684\uff0c\u5b83\u63cf\u8ff0\u4e86\u6570\u636e\u5e93\u5c06\u5982\u4f55\u6267\u884c\u67e5\u8be2\u7684\u6b65\u9aa4\u3002\u5206\u6790\u6267\u884c\u8ba1\u5212\u5bf9\u4e8e\u8bc6\u522b\u67e5\u8be2\u6027\u80fd\u95ee\u9898\u548c\u5236\u5b9a\u4f18\u5316\u7b56\u7565\u81f3\u5173\u91cd\u8981\u3002 \u6b65\u9aa4 1\uff1a\u83b7\u53d6\u6267\u884c\u8ba1\u5212 \u6839\u636e\u4e0d\u540c\u7684\u6570\u636e\u5e93\u7cfb\u7edf\uff0c\u83b7\u53d6\u6267\u884c\u8ba1\u5212\u7684\u65b9\u6cd5\u4e0d\u540c\uff1a MySQL\uff1a\u4f7f\u7528 EXPLAIN \u8bed\u53e5 PostgreSQL\uff1a\u4f7f\u7528 EXPLAIN (ANALYZE, BUFFERS) \u8bed\u53e5 Oracle\uff1a\u4f7f\u7528 EXPLAIN PLAN FOR \u8bed\u53e5 \u6b65\u9aa4 2\uff1a\u786e\u5b9a\u67e5\u8be2\u7c7b\u578b \u6267\u884c\u8ba1\u5212\u7684\u7b2c\u4e00\u884c\u63cf\u8ff0\u4e86\u67e5\u8be2\u7c7b\u578b\uff0c\u5982\uff1a SELECT\uff1a\u6570\u636e\u68c0\u7d22\u67e5\u8be2 INSERT\uff1a\u6570\u636e\u63d2\u5165\u67e5\u8be2 UPDATE\uff1a\u6570\u636e\u66f4\u65b0\u67e5\u8be2 DELETE\uff1a\u6570\u636e\u5220\u9664\u67e5\u8be2 \u6b65\u9aa4 3\uff1a\u68c0\u67e5\u8868\u626b\u63cf \u5bfb\u627e TABLE SCAN \u8868\u793a\u5168\u8868\u626b\u63cf\u3002\u8fd9\u53ef\u80fd\u8868\u660e\u9700\u8981\u521b\u5efa\u4e00\u4e2a\u7d22\u5f15\u6765\u4f18\u5316\u67e5\u8be2\u3002 \u68c0\u67e5 EXTRA \u5217\u4e2d\u7684 Using index \u6307\u793a\u662f\u5426\u4f7f\u7528\u4e86\u7d22\u5f15\u3002 \u6b65\u9aa4 4\uff1a\u5206\u6790\u8fde\u63a5 \u786e\u5b9a\u8fde\u63a5\u7c7b\u578b\uff08\u5982\u5185\u90e8\u8fde\u63a5\u3001\u5916\u90e8\u8fde\u63a5\uff09\u3002 \u68c0\u67e5\u8fde\u63a5\u6761\u4ef6\u4ee5\u786e\u4fdd\u5176\u6b63\u786e\u4e14\u9ad8\u6548\u3002 \u4f7f\u7528 ON \u5173\u952e\u5b57\u800c\u4e0d\u662f WHERE [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[16],"tags":[],"class_list":["post-5628","post","type-post","status-publish","format-standard","hentry","category-16"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/5628","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/comments?post=5628"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/5628\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=5628"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=5628"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=5628"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}