{"id":256,"date":"2024-08-21T15:25:11","date_gmt":"2024-08-21T07:25:11","guid":{"rendered":"https:\/\/note.ui11.cc\/?p=256"},"modified":"2024-08-22T08:57:05","modified_gmt":"2024-08-22T00:57:05","slug":"sql%e7%ae%80%e4%bb%8b%e5%bf%ab%e9%80%9f%e5%a4%8d%e4%b9%a0","status":"publish","type":"post","link":"https:\/\/note.ui11.cc\/index.php\/2024\/08\/21\/sql%e7%ae%80%e4%bb%8b%e5%bf%ab%e9%80%9f%e5%a4%8d%e4%b9%a0\/","title":{"rendered":"SQL\u7b80\u4ecb\u5feb\u901f\u590d\u4e60"},"content":{"rendered":"\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/note.ui11.cc\/wp-content\/uploads\/2024\/08\/image-85-1024x384.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"384\" data-original=\"https:\/\/note.ui11.cc\/wp-content\/uploads\/2024\/08\/image-85-1024x384.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-257\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<p>SQL\u8bed\u53e5\u5206\u7c7b\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/note.ui11.cc\/wp-content\/uploads\/2024\/08\/image-86-1024x300.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"300\" data-original=\"https:\/\/note.ui11.cc\/wp-content\/uploads\/2024\/08\/image-86-1024x300.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-258\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<p>\u4e00\u5171\u56db\u79cd\u5206\u522b\u4e3aDDL,DML,DQL,DCL<\/p>\n\n\n\n<p>DDL\uff1a\u6570\u636e\u5b9a\u4e49\u8bed\u8a00<\/p>\n\n\n\n<p>DML\uff1a\u6570\u636e\u64cd\u4f5c\u8bed\u8a00<\/p>\n\n\n\n<p>DQL\uff1a\u67e5\u8be2\u8bed\u8a00<\/p>\n\n\n\n<p>DCL\uff1a\u6570\u636e\u63a7\u5236\u8bed\u8a00<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/note.ui11.cc\/wp-content\/uploads\/2024\/08\/ac597f99e7224d834922ce7ef66f4f8c-1024x570.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"570\" data-original=\"https:\/\/note.ui11.cc\/wp-content\/uploads\/2024\/08\/ac597f99e7224d834922ce7ef66f4f8c-1024x570.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-259\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<p>\u8bed\u6cd5\u603b\u7ed3:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>--\u663e\u793a\u5f53\u524d\u6570\u636e\u5e93\nshow databases\n\n-- \u4f7f\u7528\u6570\u636e\u5e93\nuse xxx;\n\n--\u521b\u5efa\u6570\u636e\u5e93\ncreate database &#91;if not exists] \u6570\u636e\u5e93\u540d \n\n--\u67e5\u8be2\u6570\u636e\u5e93\u4e0b\u8868\nshow tables;\n\n-- \u663e\u793a\u8868\nshow table;\n\n-- \u521b\u5efa\u8868\ncreate table xxx;\n\n-- \u5220\u9664\u8868\ndrop table xxx;\n\n--\u67e5\u770b\u8868\u7ed3\u6784\ndescribe xxx; \u6216 desc xxx;\n\n--\u4fee\u6539\u8868\u540d\nalter table &lt;\u8868\u540d> rename &lt;\u8868\u540d>;\n\n--\u4fee\u6539\u8868\u5b57\u6bb5\u4fe1\u606f\nalter table \u8868\u540d change \u5b57\u6bb5\u540d   \u4fee\u6539\u540e\u7684\u5217\u540d\u548c\u5c5e\u6027;\n\n--\u589e\u52a0\u8868\u5b57\u6bb5\u4fe1\u606f\nalter table \u8868\u540d add  \u5b57\u6bb5\u540d\u53ca\u5c5e\u6027\n\n--\u5220\u9664\u4e00\u4e2a\u8868\u5b57\u6bb5\nalter table \u8868\u540d drop \u5b57\u6bb5\u540d;\n\n--\u63d2\u5165\u6570\u636e\ninsert into \u8868\u540d value(\u6839\u636e\u8868\u7ed3\u6784\u63d2\u5165\u6570\u636e\u5185\u5bb9 );\n\n--\u63d2\u5165\u6570\u636e,\u6307\u5b9a\u5c5e\u6027\ninsert into \u8868\u540d (\u5217\u540d) value(\u6839\u636e\u8868\u7ed3\u6784\u63d2\u5165\u6570\u636e\u5185\u5bb9 );\n\n--\u4fee\u6539\u6570\u636e\nupdate \u8868 set \u5b57\u6bb51=value1, \u5b57\u6bb52=value2... where \u6761\u4ef6\n\n--\u5220\u9664\u6570\u636e\ndelete from \u8868 where \u6761\u4ef6 \n\n--\u67e5\u770b\u7d22\u5f15\nshow index from \u8868\u540d;\n\n--\u521b\u5efa\u7d22\u5f15 \u5bf9\u4e8e\u975e\u4e3b\u952e\u3001\u975e\u552f\u4e00\u7ea6\u675f\u3001\u975e\u5916\u952e\u7684\u5b57\u6bb5\uff0c\u53ef\u4ee5\u521b\u5efa\u666e\u901a\u7d22\u5f15\ncreate index \u7d22\u5f15\u540d on \u8868\u540d(\u5b57\u6bb5\u540d);\n\n--\u5220\u9664\u7d22\u5f15\ndrop index \u7d22\u5f15\u540d on \u8868\u540d;\n\n--\u4e8b\u52a1\n\u90a3\u5c31\u8ba9\u8fd9\u91cc\u4e24\u4e2a\u64cd\u4f5c\u8981\u4e48\u540c\u65f6\u6210\u529f\uff0c\u8981\u4e48\u540c\u65f6\u5931\u8d25\u3002\u8fd9\u5c31\u662f\u4e8b\u52a1\u7684\u903b\u8f91\u3002\n\uff081\uff09\u5f00\u542f\u4e8b\u52a1\uff1astart transaction\uff1b\n\uff082\uff09\u4e2d\u95f4\u6267\u884c\u591a\u6761SQL\u8bed\u53e5\n\uff083\uff09\u56de\u6eda\u6216\u63d0\u4ea4\uff1arollback\/commit;\n\n-- \u5168\u5217\u67e5\u8be2\nselect * from \u8868\n\n-- \u6307\u5b9a\u5217\u67e5\u8be2\nselect \u5b57\u6bb51,\u5b57\u6bb52... from \u8868\n\n-- \u67e5\u8be2\u8868\u8fbe\u5f0f\u5b57\u6bb5\nselect \u5b57\u6bb51+100,\u5b57\u6bb52+\u5b57\u6bb53 from \u8868\n\n-- \u522b\u540d\nselect \u5b57\u6bb51 \u522b\u540d1, \u5b57\u6bb52 \u522b\u540d2 from \u8868\n\n-- \u53bb\u91cdDISTINCT\nselect distinct \u5b57\u6bb5 from \u8868\n\n-- \u6392\u5e8fORDER BY\nselect * from \u8868 order by \u6392\u5e8f\u5b57\u6bb5\n\n-- \u6761\u4ef6\u67e5\u8be2where\uff1a\n(1)\u6bd4\u8f83\u8fd0\u7b97\u7b26 (2)BETWEEN ... AND ... (3)IN (4)IS NULL (5)LIKE (6)AND (7)OR(8)NOT\nselect * from \u8868 where \u6761\u4ef6\n>, >=, &lt;, &lt;=,=,&lt;=>(\u7b49\u4e8e),!=, &lt;>\nbetween a and b,IS NULL,IS NOT NULL\nIN (option, ...)    \u5982\u679c\u662f option \u4e2d\u7684\u4efb\u610f\u4e00\u4e2a\uff0c\u8fd4\u56de TRUE(1)\nLIKE    \u6a21\u7cca\u5339\u914d\u3002% \u8868\u793a\u4efb\u610f\u591a\u4e2a\uff08\u5305\u62ec 0 \u4e2a\uff09\u4efb\u610f\u5b57\u7b26\uff1b_ \u8868\u793a\u4efb\u610f\u4e00\u4e2a\u5b57\u7b26\n\u903b\u8f91\u8fd0\u7b97\u7b26:and,or,not\n\n--\u5206\u9875\u67e5\u8be2limit--\u4ece s \u5f00\u59cb\uff0c\u7b5b\u9009 n \u6761\u7ed3\u679c\uff0c\u6bd4\u7b2c\u4e8c\u79cd\u7528\u6cd5\u66f4\u660e\u786e\uff0c\u5efa\u8bae\u4f7f\u7528\nselect ... from \u8868\u540d&#91;where...]&#91;order by..] limit s offset n;\n\n--\u805a\u5408\u51fd\u6570\nCOUNT(&#91;DISTINCT] expr)(\u8ba1\u6570),SUM(&#91;DISTINCT] expr),AVG(&#91;DISTINCT] expr),MAX(&#91;DISTINCT] expr),MIN(&#91;DISTINCT] expr)\nselect role,max(salary),min(salary),avg(salary) from emp group by role\uff1b\n\n--group by  \u5206\u7ec4\u67e5\u8be2 having \u6761\u4ef6\u8fc7\u6ee4\nGROUP BY \u5b50\u53e5\u8fdb\u884c\u5206\u7ec4\u4ee5\u540e\uff0c\u9700\u8981\u5bf9\u5206\u7ec4\u7ed3\u679c\u518d\u8fdb\u884c\u6761\u4ef6\u8fc7\u6ee4\u65f6\uff0c\u4e0d\u80fd\u4f7f\u7528 WHERE \u8bed\u53e5\uff0c\u800c\u9700\u8981\u7528HAVING\n\u663e\u793a\u5e73\u5747\u5de5\u8d44\u4f4e\u4e8e1500\u7684\u89d2\u8272\u548c\u5b83\u7684\u5e73\u5747\u5de5\u8d44\nselect role,max(salary),min(salary),avg(salary) from emp group by role\nhaving avg(salary)&lt;1500;\n\n--\u8054\u5408\u67e5\u8be2\n--\u5185\u8fde\u63a5\nselect \u5b57\u6bb5 from \u88681 \u522b\u540d1 &#91;inner] join \u88682 \u522b\u540d2 on \u8fde\u63a5\u6761\u4ef6 and \u5176\u4ed6\u6761\u4ef6;\nselect \u5b57\u6bb5 from \u88681 \u522b\u540d1,\u88682 \u522b\u540d2 where \u8fde\u63a5\u6761\u4ef6 and \u5176\u4ed6\u6761\u4ef6;\n\n-- \u5de6\u5916\u8fde\u63a5\uff0c\u88681\u5b8c\u5168\u663e\u793a\nselect \u5b57\u6bb5\u540d from \u8868\u540d1 left join \u8868\u540d2 on \u8fde\u63a5\u6761\u4ef6;\n\n-- \u53f3\u5916\u8fde\u63a5\uff0c\u88682\u5b8c\u5168\u663e\u793a\nselect \u5b57\u6bb5 from \u8868\u540d1 right join \u8868\u540d2 on \u8fde\u63a5\u6761\u4ef6;\n\n--\u81ea\u8fde\u63a5,\u81ea\u8fde\u63a5\u662f\u6307\u5728\u540c\u4e00\u5f20\u8868\u8fde\u63a5\u81ea\u8eab\u8fdb\u884c\u67e5\u8be2\u3002\nselect \u5b57\u6bb5 from \u88681 \u522b\u540d1 join \u88681 \u522b\u540d2 on \u8fde\u63a5\u6761\u4ef6  join \u88682 \u522b\u540d1 on \u6761\u4ef6 join \u886812\u522b\u540d2 .......and \u5176\u4ed6\u6761\u4ef6;\n\n--\u5b50\u67e5\u8be2\n-- \u5355\u884c\u5b50\u67e5\u8be2\nselect ... from \u88681 where \u5b57\u6bb51 = (select ... from ...);\n\n--\u591a\u884c\u5b50\u67e5\u8be2\n-- &#91;NOT] IN\nselect ... from \u88681 where \u5b57\u6bb51 in (select ... from ...);\n-- &#91;NOT] EXISTS\nselect ... from \u88681 where exists (select ... from ... where \u6761\u4ef6);\n\n-- \u4e34\u65f6\u8868\uff1aform\u5b50\u53e5\u4e2d\u7684\u5b50\u67e5\u8be2\nselect ... from \u88681\uff0c (select ... from ...) as tmp where \u6761\u4ef6\n\u5728from\u5b50\u53e5\u4e2d\u4f7f\u7528\u5b50\u67e5\u8be2\uff1a\u5b50\u67e5\u8be2\u8bed\u53e5\u51fa\u73b0\u5728from\u5b50\u53e5\u4e2d\u3002\u8fd9\u91cc\u8981\u7528\u5230\u6570\u636e\u67e5\u8be2\u7684\u6280\u5de7\uff0c\u628a\u4e00\u4e2a\u5b50\u67e5\u8be2\u5f53\u505a\u4e00\u4e2a\u4e34\u65f6\u8868\u4f7f\u7528\u3002\n\n----\u5728from\u5b50\u53e5\u4e2d\u4f7f\u7528\u5b50\u67e5\u8be2\uff1a\u5b50\u67e5\u8be2\u8bed\u53e5\u51fa\u73b0\u5728from\u5b50\u53e5\u4e2d\u3002\u8fd9\u91cc\u8981\u7528\u5230\u6570\u636e\u67e5\u8be2\u7684\u6280\u5de7\uff0c\u628a\u4e00\u4e2a\u5b50\u67e5\u8be2\u5f53\u505a\u4e00\u4e2a\u4e34\u65f6\u8868\u4f7f\u7528\u3002\n-- UNION\uff1a\u53bb\u9664\u91cd\u590d\u6570\u636e\uff08\u64cd\u4f5c\u7b26\u7528\u4e8e\u53d6\u5f97\u4e24\u4e2a\u7ed3\u679c\u96c6\u7684\u5e76\u96c6\u3002\u5f53\u4f7f\u7528\u8be5\u64cd\u4f5c\u7b26\u65f6\uff0c\u4f1a\u81ea\u52a8\u53bb\u6389\u7ed3\u679c\u96c6\u4e2d\u7684\u91cd\u590d\u884c\u3002\uff09\nselect ... from ... where \u6761\u4ef6\nunion\nselect ... from ... where \u6761\u4ef6\n\n-- UNION ALL\uff1a\u4e0d\u53bb\u91cd\uff08\u8be5\u64cd\u4f5c\u7b26\u7528\u4e8e\u53d6\u5f97\u4e24\u4e2a\u7ed3\u679c\u96c6\u7684\u5e76\u96c6\u3002\u5f53\u4f7f\u7528\u8be5\u64cd\u4f5c\u7b26\u65f6\uff0c\u4e0d\u4f1a\u53bb\u6389\u7ed3\u679c\u96c6\u4e2d\u7684\u91cd\u590d\u884c\uff09\nselect ... from ... where \u6761\u4ef6\nunion all\nselect ... from ... where \u6761\u4ef6\n\u4f7f\u7528UNION\u548cUNION ALL\u65f6\uff0c\u524d\u540e\u67e5\u8be2\u7684\u7ed3\u679c\u96c6\u4e2d\uff0c\u5b57\u6bb5\u9700\u8981\u4e00\u81f4\n\n\n--\u6570\u636e\u5e93\u7ea6\u675f\nNOT NULL - \u6307\u793a\u67d0\u5217\u4e0d\u80fd\u4e3a\u7a7a\nUNIQUE - \u4fdd\u8bc1\u67d0\u5217\u7684\u6bcf\u884c\u5fc5\u987b\u6709\u552f\u4e00\uff0c\u4e0d\u91cd\u590d\u7684\u3002\nDEFAULT - \u89c4\u5b9a\u6ca1\u6709\u7ed9\u5217\u8d4b\u503c\u65f6\u7684\u9ed8\u8ba4\u503c\u3002\nPRIMARY KEY - \u4e3b\u952e\u7ea6\u675f\uff0c\u4e0e NOT NULL \u548c UNIQUE \u7684\u7ed3\u5408\u3002\u786e\u4fdd\u67d0\u5217\uff08\u6216\u4e24\u4e2a\u5217\u591a\u4e2a\u5217\u7684\u7ed3\u5408\uff09\u6709\u552f\u4e00\u6807\u8bc6\uff0c\u6709\u52a9\u4e8e\u66f4\u5bb9\u6613\u66f4\u5feb\u901f\u5730\u627e\u5230\u8868\u4e2d\u7684\u4e00\u4e2a\u7279\u5b9a\u7684\u8bb0\u5f55\u3002\nFOREIGN KEY - \u5916\u952e\u7ea6\u675f\uff0c\u4fdd\u8bc1\u4e00\u4e2a\u8868\u4e2d\u7684\u6570\u636e\u5339\u914d\u53e6\u4e00\u4e2a\u8868\u4e2d\u7684\u503c\u7684\u53c2\u7167\u5b8c\u6574\u6027\u3002\nCHECK - \u4fdd\u8bc1\u5217\u4e2d\u7684\u503c\u7b26\u5408\u6307\u5b9a\u7684\u6761\u4ef6\u3002\u5bf9\u4e8eMySQL\u6570\u636e\u5e93\uff0c\u5bf9CHECK\u5b50\u53e5\u8fdb\u884c\u5206\u6790\uff0c\u4f46\u662f\u5ffd\u7565CHECK\u5b50\u53e5\u3002\n\n\n   \n\n<\/code><\/pre>\n\n\n\n<p><\/p>\n\n\n\n<p><\/p>\n\n\n\n<p><\/p>\n\n\n\n<p><\/p>\n\n\n\n<p><\/p>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>SQL\u8bed\u53e5\u5206\u7c7b\uff1a \u4e00\u5171\u56db\u79cd\u5206\u522b\u4e3aDDL,DML,DQL,DCL DDL\uff1a\u6570\u636e\u5b9a\u4e49\u8bed\u8a00 DML\uff1a\u6570\u636e\u64cd\u4f5c\u8bed\u8a00 D [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-256","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/note.ui11.cc\/index.php\/wp-json\/wp\/v2\/posts\/256","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/note.ui11.cc\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/note.ui11.cc\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/note.ui11.cc\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/note.ui11.cc\/index.php\/wp-json\/wp\/v2\/comments?post=256"}],"version-history":[{"count":2,"href":"https:\/\/note.ui11.cc\/index.php\/wp-json\/wp\/v2\/posts\/256\/revisions"}],"predecessor-version":[{"id":269,"href":"https:\/\/note.ui11.cc\/index.php\/wp-json\/wp\/v2\/posts\/256\/revisions\/269"}],"wp:attachment":[{"href":"https:\/\/note.ui11.cc\/index.php\/wp-json\/wp\/v2\/media?parent=256"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/note.ui11.cc\/index.php\/wp-json\/wp\/v2\/categories?post=256"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/note.ui11.cc\/index.php\/wp-json\/wp\/v2\/tags?post=256"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}