{"id":127,"date":"2022-10-25T00:27:13","date_gmt":"2022-10-24T16:27:13","guid":{"rendered":"https:\/\/www.6665544.xyz\/?p=127"},"modified":"2022-10-25T00:28:44","modified_gmt":"2022-10-24T16:28:44","slug":"mysql-%e7%ac%94%e8%ae%b0%ef%bc%88%e6%9b%b4%e6%96%b0%e5%88%b022-10-24%ef%bc%89","status":"publish","type":"post","link":"https:\/\/www.6665544.xyz\/?p=127","title":{"rendered":"Mysql-\u7b14\u8bb0\uff08\u66f4\u65b0\u523022-10-24\uff09"},"content":{"rendered":"\n
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show databases; \u67e5\u770b\u6240\u6709\u8868<\/span><\/span>\nuse<\/span>  <\/span><<\/span>\u8868<\/span>><\/span>; \u8fdb\u53bb\u6570\u636e\u5e93<\/span><\/span>\nshow tables; \u67e5\u8be2\u5f53\u524d\u6570\u636e\u5e93\u7684\u8868<\/span><\/span>\ndesc<\/span> <\/span><<\/span>\u8868\u540d<\/span>><\/span>   \u67e5\u8be2\u5f53\u524d\u8868\u5185\u6570\u636e<\/span><\/span>\n<\/span>\n<\/span>\n<\/span>\n\u67e5\u8be2\u8bed\u53e5 <\/span><\/span>\nselect<\/span> <\/span>*<\/span> <\/span>from<\/span> \u8868\u540d  \u67e5\u8be2\u8868\u7684\u5168\u90e8\u6570\u636e<\/span><\/span>\n<\/span>\n\u521b\u5efa\u6570\u636e\u5e93<\/span><\/span>\ncreate<\/span>  <\/span>database<\/span> d_sample;<\/span><\/span>\n<\/span>\n<\/span>\n<\/span>\n\u521b\u5efa\u8868\u7684\u6570\u636e<\/span><\/span>\ncreate<\/span> <\/span>table<\/span> student(   <\/span><\/span>\nchar<\/span>(<\/span>9<\/span>) <\/span>primary<\/span> <\/span>key<\/span>,<\/span><\/span>\nvarchar<\/span>(<\/span>10<\/span>),<\/span><\/span>\nchar<\/span>(<\/span>2<\/span>),<\/span><\/span>\ndate<\/span>,<\/span><\/span>\nvarchar<\/span>(<\/span>10<\/span>),<\/span><\/span>\nvarchar<\/span>(<\/span>8<\/span>)<\/span><\/span>\n);<\/span><\/span>\n<\/span>\nALTER<\/span> <\/span>TABLE<\/span> <\/span><<\/span>\u8981\u4fee\u6539\u8868\u7684\u6635\u79f0<\/span>><\/span><\/span>\nADD<<\/span>\u65b0\u5b57\u6bb5\u540d<\/span>><<\/span>\u6570\u636e\u7c7b\u578b<\/span>><\/span>(\u957f\u5ea6)<\/span><<\/span>\u7ea6\u675f\u6761\u4ef6<\/span>><\/span><\/span>\nADD<\/span> <\/span>INDEX<<\/span>\u68c0\u7d22\u540d<\/span>><\/span><\/span>\nDROP<<\/span>\u5b57\u6bb5\u540d<\/span>>OR<<\/span>\u68c0\u7d22\u540d<\/span>><\/span>    \u5220\u9664\u5b57\u6bb5<\/span><\/span>\nDROP<\/span> <\/span>TABLE<\/span> <\/span><<\/span>\u8868\u540d<\/span>><\/span>   \u5220\u9664\u8868<\/span><\/span>\n<\/span>\nRENAME <\/span>AS<<\/span>\u65b0\u8868\u540d\u5b57<\/span>><\/span> <\/span><\/span>\nmodify<\/span> <\/span><<\/span>\u8981\u4fee\u6539\u7684\u5b57\u6bb5\u540d<\/span>><<\/span>\u65b0\u6570\u636e\u7c7b\u578b<\/span>><\/span>   \u6539<\/span><\/span>\n<\/span>\n<\/span>\n\u5411\u8868\u63d2\u5165\u6570\u636e<\/span><\/span>\ninsert<\/span> <\/span>into<\/span> <\/span><<\/span>\u8868\u540d<\/span>><\/span>[\u5b57\u6bb5\u540d] <\/span>values<\/span> [\u6570\u636e]  <\/span><\/span>\n\u4f8b\u5b50\uff1a<\/span><\/span>\ninsert<\/span> <\/span>into<\/span> student <\/span>values<\/span><\/span>\n(<\/span>'2010502'<\/span>,<\/span>'\u7f51\u4e09'<\/span>,<\/span>'W'<\/span>,<\/span>'2000-01-05'<\/span>,<\/span>'25'<\/span>,<\/span>'50'<\/span>);<\/span><\/span>\n<\/span>\n\u66f4\u65b0\u6570\u636e<\/span><\/span>\nupdate<\/span> <\/span><<\/span>\u8868\u540d<\/span>><\/span> <\/span>set<\/span> <\/span><<\/span>\u5b57\u6bb5\u540d<\/span>><\/span> <\/span>=<<\/span>\u8868\u8fbe\u5f0f<\/span>><\/span> <\/span>where<\/span> <\/span><<\/span>\u6761\u4ef6<\/span>><\/span><\/span>\n\u5177\u4f53\u4f8b\u5b50\uff1a<\/span><\/span>\nupdate<\/span> student <\/span>set<\/span> age<\/span>=<\/span>'21'<\/span> <\/span>where<\/span> sanme<\/span>=<\/span>"zhangsan02"<\/span><\/span>\nupdate<\/span> student <\/span>set<\/span> score <\/span>=<\/span> <\/span>100<\/span>;<\/span><\/span>\n<\/span>\n\u5220\u9664\u6570\u636e<\/span><\/span>\ndetele <\/span>from<\/span> <\/span><<\/span>\u8868\u540d<\/span>><\/span> [where <\u6761\u4ef6>]<\/span><\/span>\n<\/span>\n<\/span>\n\u7ea6\u675f<\/span><\/span>\nshow <\/span>create<\/span> <\/span>table<\/span> student;<\/span><\/span>\n\u5b9a\u4e49\u7ea6\u675f<\/span><\/span>\nPRIMARY<\/span> <\/span>KEY<\/span> \u7ea6\u675f<\/span><\/span>\n\u65b9\u5f0f\u4e00\uff1a<\/span>create<\/span> <\/span>table<\/span> <\/span><<\/span>\u8868\u540d<\/span>><\/span>\uff08<\/span><\/span>\n\u5b57\u6bb51  <\/span>primary<\/span> <\/span>key\/\/<\/span>\u7b2c\u4e00\u79cd\u6dfb\u52a0\u4e3b\u952e<\/span><\/span>\n\u5b57\u6bb52<\/span><\/span>\n\u5b57\u6bb5n\u3002\u3002<\/span><\/span>\nconstraint<\/span> p\u5b57\u6bb5\u540d <\/span>primary<\/span> <\/span>key<\/span> (\u5b57\u6bb5\u540d)<\/span>\/\/<\/span>\u7b2c\u4e8c\u79cd\u6dfb\u52a0\u4e3b\u952e \u7ea6\u675f<\/span><\/span>\n)<\/span><\/span>\n<\/span>\n\u65b9\u5f0f\u4e8c\uff1a<\/span>alter<\/span> <\/span>table<\/span> <\/span><<\/span>\u8868\u540d<\/span>><\/span> <\/span>add<\/span> <\/span>constraint<\/span> <\/span><<\/span>\u7ea6\u675f\u540d\u79f0<\/span>><<\/span>\u7ea6\u675f\u7c7b\u578b<\/span>><\/span>\uff08\u5b57\u6bb5\u540d\uff09<\/span><\/span>\n<\/span>\n\u5220\u9664\u7ea6\u675f\uff1a<\/span><\/span>\nalter<\/span> <\/span>table<\/span> <\/span><<\/span>\u8868\u660e<\/span>>drop<\/span> <\/span>constraint<\/span> <\/span><<\/span>\u7ea6\u675f\u540d\u79f0<\/span>><\/span>\uff1b<\/span>\/\/<\/span>\u901a\u7528<\/span><\/span>\nalter<\/span> <\/span>table<\/span> <\/span><<\/span>\u8868\u660e<\/span>>drop<\/span>  <\/span>primary<\/span> <\/span>key<\/span>\uff1b <\/span>\/\/<\/span>\u4e3b\u952e\u7684<\/span><\/span>\n<\/span>\nunique<\/span> \u7ea6\u675f <\/span>\/\/<\/span>\u552f\u4e00<\/span><\/span>\n\u65b9\u5f0f\u4e00\uff1a<\/span>create<\/span> <\/span>table<\/span> <\/span><<\/span>\u8868\u540d<\/span>><\/span>\uff08<\/span><\/span>\n\u5b57\u6bb51  <\/span>unique\/\/<\/span>\u7b2c\u4e00\u79cd\u6dfb\u52a0\u552f\u4e00<\/span><\/span>\n\u5b57\u6bb52<\/span><\/span>\n\u5b57\u6bb5n\u3002\u3002<\/span><\/span>\nconstraint<\/span> usocialno  <\/span>unique<\/span> (\u5b57\u6bb5\u540d)<\/span>\/\/<\/span>\u7b2c\u4e8c\u79cd\u6dfb\u52a0\u552f\u4e00 \u7ea6\u675f<\/span><\/span>\n)<\/span><\/span>\n<\/span>\n\u65b9\u5f0f\u4e8c\uff1a<\/span>alter<\/span> <\/span>table<\/span> student <\/span>add<\/span> <\/span>unique<\/span>(sname);<\/span><\/span>\n<\/span>\n\u5220\u9664\u7ea6\u675f\uff1a<\/span><\/span>\nalter<\/span> <\/span>table<\/span> student <\/span>drop<\/span> <\/span>index<\/span> sname;<\/span><\/span>\nalter<\/span> <\/span>table<\/span> student <\/span>drop<\/span> <\/span>constraint<\/span> sname;<\/span><\/span>\n<\/span>\n<\/span>\ncheck\u7ea6\u675f   \u7528\u6765\u786e\u5b9a\u6570\u636e\u8303\u56f4\u7684\u7ea6\u675f<\/span><\/span>\nconstraint<\/span>  cscore cherk(score <\/span>between<\/span> <\/span>0<\/span> <\/span>and<\/span> <\/span>100<\/span>)<\/span><\/span>\n<\/span>\nforeign key<\/span> \u7ea6\u675f <\/span><\/span>\n\u5916\u952e\u7ea6\u675f \u7528\u6765\u786e\u4fdd\u53c2\u7167\u5b8c\u6574\u6027<\/span><\/span>\nconstraint<\/span> <\/span><<\/span>\u7ea6\u675f\u540d<\/span>><\/span> <\/span>foreign key<\/span> <\/span><<\/span>\u5b57\u6bb5\u540d<\/span>><\/span> <\/span>references<\/span> <\/span><<\/span>\u8868\u540d<\/span>><><\/span><\/span>\n<\/span>\n<\/span>\nNOT<\/span> <\/span>NUll<\/span> \u7ea6\u675f<\/span><\/span>\n<\/span>\n-----not null<\/span><\/span>\n\u975e\u7a7a\u7ea6\u675f<\/span><\/span>\n\u5728\u521b\u5efa\u8868\u7684\u65f6\u5019 \u8bbe\u7f6e\u67d0\u4e9b\u5b57\u6bb5\u540d\u4e3a\u975e\u7a7a<\/span><\/span>\n<\/span>\n<\/span>\nDEFAULT<\/span> \u7ea6\u675f<\/span><\/span>\n\u9ed8\u8ba4\u503c\u7ea6\u675f  \u4e3a\u7279\u5b9a\u5c5e\u6027\u8bbe\u7f6e\u9ed8\u8ba4\u503c<\/span><\/span>\n----- default 'XXXX' \/\/\u65b9\u5f0f1<\/span><\/span>\nalter<\/span> <\/span>table<\/span> \u8bed\u53e5<\/span>\/\/<\/span>\u540e\u9762\u52a0<\/span><\/span>\n<\/span>\n<\/span>\n<\/span>\n<\/span>\n<\/span><\/code><\/pre><\/div>\n","protected":false},"excerpt":{"rendered":"
\u6742\u4e71\u7684\u7b14\u8bb0<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"emotion":"","emotion_color":"","title_style":"","license":"","footnotes":""},"categories":[27,28],"tags":[25,30],"class_list":["post-127","post","type-post","status-publish","format-standard","hentry","category-mysql","category-28","tag-mysql","tag-30"],"_links":{"self":[{"href":"https:\/\/www.6665544.xyz\/index.php?rest_route=\/wp\/v2\/posts\/127","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.6665544.xyz\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.6665544.xyz\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.6665544.xyz\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.6665544.xyz\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=127"}],"version-history":[{"count":3,"href":"https:\/\/www.6665544.xyz\/index.php?rest_route=\/wp\/v2\/posts\/127\/revisions"}],"predecessor-version":[{"id":130,"href":"https:\/\/www.6665544.xyz\/index.php?rest_route=\/wp\/v2\/posts\/127\/revisions\/130"}],"wp:attachment":[{"href":"https:\/\/www.6665544.xyz\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=127"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.6665544.xyz\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=127"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.6665544.xyz\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=127"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}