{"id":78,"date":"2025-01-17T22:05:24","date_gmt":"2025-01-17T14:05:24","guid":{"rendered":"http:\/\/gzxingyu.cloud\/?p=78"},"modified":"2025-10-21T21:10:38","modified_gmt":"2025-10-21T13:10:38","slug":"mysql%e6%95%b0%e6%8d%ae%e5%ba%93%e5%a2%9e%e5%88%a0%e6%94%b9%e6%9f%a5","status":"publish","type":"post","link":"http:\/\/gzxingyu.cloud\/index.php\/2025\/01\/17\/mysql%e6%95%b0%e6%8d%ae%e5%ba%93%e5%a2%9e%e5%88%a0%e6%94%b9%e6%9f%a5\/","title":{"rendered":"Mysql\u6570\u636e\u5e93\u589e\u5220\u6539\u67e5"},"content":{"rendered":"

1\u3001mysql\u6570\u636e\u5e93\u589e\u64cd\u4f5c<\/h3>\n

\"Pasted<\/div><\/p>\n

\uff081\uff09\u65b0\u589e\u547d\u4ee4create<\/h4>\n

1\u3001create database \u5e93\u540d;\u00a0 \u521b\u5efa\u6570\u636e\u5e93<\/p>\n

2\u3001Create database \u5e93\u540d character set utf8;\u00a0 \u6307\u5b9a\u7f16\u7801\u6570\u636e\u5e93 utf-8
\n

\"Pasted<\/div><\/p>\n

3\u3001Use \u5e93\u540d;\u00a0 \u6307\u5b9a\u6570\u636e\u5e93
\n

\"Pasted<\/div><\/p>\n

4\u3001\u521b\u5efa\u8868<\/p>\n

Create table \u8868\u540d(<\/p>\n

\u5b57\u6bb5\u540d1\u00a0 \u6570\u636e\u7c7b\u578b(\u5b57\u8282\u6570),\u00a0 \u5982\u00a0\u00a0\u00a0 id\u00a0 int(11),<\/p>\n

\u5b57\u6bb5\u540d2\u00a0 \u6570\u636e\u7c7b\u578b(\u5b57\u8282\u6570),\u00a0 username\u00a0 verchar(50),<\/p>\n

……………<\/p>\n

);
\n

\"Pasted<\/div><\/p>\n

5\u3001\u63d2\u5165\u6570\u636e<\/p>\n

Insert into \u8868\u540d(\u5b57\u6bb51,\u5b57\u6bb52\uff0c\u5b57\u6bb53…….) values(\u503c1,\u503c2,………)\u00a0 \u6ce8\u610f\u5b57\u7b26\u578b\u8981\u6253\u2019\u2019\u8fd9\u4e2a\u7b26\u53f7
\n

\"Pasted<\/div><\/p>\n

\u7b2c\u4e8c\u79cd\u5199\u6cd5<\/p>\n

Insert into \u8868\u540d set \u5b57\u6bb51=\u503c1, \u5b57\u6bb52=\u503c2\u00a0 \u6ce8\u610f\u5b57\u7b26\u578b
\n

\"Pasted<\/div><\/p>\n

\u540c\u65f6\u63d2\u5165\u591a\u6761\u6570\u636e<\/p>\n

Insert into \u8868\u540d(\u5b57\u6bb51,\u5b57\u6bb52\uff0c\u5b57\u6bb53…….) values(\u503c1,\u503c2,………),(\u503c1,\u503c2,………),(\u503c1,\u503c2,………);
\n

\"Pasted<\/div><\/p>\n

\uff082\uff09\u5220\u9664\u547d\u4ee4Drop<\/h4>\n

1\u3001Drop database \u5e93\u540d;\u00a0 \u5220\u9664\u6570\u636e\u5e93
\n

\"Pasted<\/div><\/p>\n

2\u3001drop table \u8868\u540d;\u00a0 \u5220\u9664\u8868<\/p>\n

3\u3001delete from \u8868\u540d where \u5b57\u6bb5 = \u503c;\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0 \u5220\u9664\u6570\u636e
\n

\"Pasted<\/div>
\nwhere\uff08\u5224\u65ad\uff09
\n
\"Pasted<\/div>
\ndelete from user \u5220\u5e93<\/p>\n

\uff083\uff09\u67e5\u8be2\u547d\u4ee4select<\/h4>\n

1\u3001show databases;\u00a0 \u67e5\u770b\u5b58\u5728\u7684\u6570\u636e\u5e93<\/p>\n

2\u3001Use \u6570\u636e\u5e93\u540d;\u00a0 \u00a0 \u6307\u5b9a\u6570\u636e\u5e93<\/p>\n

3\u3001\u67e5\u8be2\u8bed\u53e5<\/p>\n

Select \u5b57\u6bb51\uff0c\u5b57\u6bb52\uff0c\u5b57\u6bb53 from \u8868\u540d\u00a0 where \u6761\u4ef6;<\/p>\n

\u5982 select username form abc where id =1 \u00a0 \u8fd9\u4e2a\u7684\u610f\u601d\u662f\u00a0 \u67e5\u8be2abc\u8868\u4e2d\u00a0 id =1 \u7684 username \u6570\u636e<\/p>\n

Select * from \u8868\u540d;\u00a0 \u4ee3\u8868\u67e5\u8be2\u8868\u91cc\u6240\u6709\u6570\u636e
\n4\u3001\u67e5\u8be2\u8d77\u522b\u540d<\/p>\n

Select username a from \u8868\u540d where \u6761\u4ef6;\u00a0 a\u5c31\u662fusername\u7684\u522b\u540d<\/p>\n

\u67e5\u8be2\u51fd\u6570 \u51fd\u6570\u662f\u6307\u4e00\u6bb5\u53ef\u4ee5\u76f4\u63a5\u88ab\u53e6\u4e00\u6bb5\u7a0b\u5e8f\u6216\u4ee3\u7801\u5f15\u7528\u7684\u7a0b\u5e8f\u6216\u4ee3\u7801\u3002<\/p>\n

5\u3001Select current_user();\u00a0 \u00a0 \u5f53\u524d\u7528\u6237\u540d<\/p>\n

6\u3001select session_user();\u00a0 \u8fde\u63a5\u6570\u636e\u5e93\u7684\u7528\u6237\u540d<\/p>\n

7\u3001select @@basedir;\u00a0 \u00a0 mysql\u5b89\u88c5\u8def\u5f84<\/p>\n

8\u3001select @@datadir;\u00a0 \u6570\u636e\u5e93\u8def\u5f84<\/p>\n

9\u3001select @@version_compile_os;\u00a0 \u64cd\u4f5c\u7cfb\u7edf\u7248\u672c<\/p>\n

\u5b57\u7b26\u4e32\u8fde\u63a5\u51fd\u6570<\/h5>\n

concat(),concat_ws(),group_concat()<\/p>\n

10\u3001select concat(id,’|’,username,’|’,password) from users;<\/p>\n

11\u3001select concat_ws(‘|’,id,username,password) from users;<\/p>\n

12\u3001select group_concat(‘\\n’,username) from users;<\/p>\n

\u5b57\u7b26\u4e32\u622a\u53d6\u51fd\u6570<\/h5>\n

13\u3001select substr((select username from users limit 0,1),1,2);<\/p>\n

\/\/\u4ee3\u8868\u4eceusers\u4e2dusername\u7b2c\u4e00\u6761\u6570\u636e\u4ece\u7b2c\u4e00\u4f4d\u5f00\u59cb\u622a\u53d6\uff0c\u622a\u53d6\u4e24\u4f4d\u6570<\/p>\n

14\u3001select mid(‘martin’,2,3);\u00a0 \u00a0 \/\/\u4ee3\u8868\u501f\u52a9MID\u51fd\u6570\u4ece\u5b57\u7b26\u4e32\u2018martin\u2019\u4e2d\u4ece\u7b2c\u4e8c\u4f4d\u5f00\u59cb\uff0c\u63d0\u53d6\u957f\u5ea6\u4e3a5\u7684\u5b57\u7b26\u4e32\u3002<\/p>\n

15\u3001select left(‘martin’,2);<\/p>\n

\/\/\u4ee3\u8868\u4ece\u5de6\u6570\u7b2c\u4e8c\u4f4d<\/p>\n

16\u3001select right(‘martin’,2);<\/p>\n

\/\/\u4ee3\u8868\u4ece\u53f3\u6570\u7b2c\u4e8c\u4f4d<\/p>\n

17\u3001select locate(‘security’,’1234security’);<\/p>\n

\/\/\u8fd4\u56de\u5b57\u7b26\u4e32security\u4e2d\u7b2c\u4e00\u6b21\u51fa\u73b0\u5b50\u5b57\u7b26\u4e32\u7684\u4f4d\u7f6e<\/p>\n","protected":false},"excerpt":{"rendered":"

1\u3001mysql\u6570\u636e\u5e93\u589e\u64cd\u4f5c \uff081\uff09\u65b0\u589e\u547d\u4ee4create 1\u3001create database \u5e93\u540d;\u00a0 \u521b\u5efa\u6570\u636e […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5,4],"tags":[],"class_list":["post-78","post","type-post","status-publish","format-standard","hentry","category-sql","category-web"],"_links":{"self":[{"href":"http:\/\/gzxingyu.cloud\/index.php\/wp-json\/wp\/v2\/posts\/78","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/gzxingyu.cloud\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/gzxingyu.cloud\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/gzxingyu.cloud\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/gzxingyu.cloud\/index.php\/wp-json\/wp\/v2\/comments?post=78"}],"version-history":[{"count":2,"href":"http:\/\/gzxingyu.cloud\/index.php\/wp-json\/wp\/v2\/posts\/78\/revisions"}],"predecessor-version":[{"id":84,"href":"http:\/\/gzxingyu.cloud\/index.php\/wp-json\/wp\/v2\/posts\/78\/revisions\/84"}],"wp:attachment":[{"href":"http:\/\/gzxingyu.cloud\/index.php\/wp-json\/wp\/v2\/media?parent=78"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/gzxingyu.cloud\/index.php\/wp-json\/wp\/v2\/categories?post=78"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/gzxingyu.cloud\/index.php\/wp-json\/wp\/v2\/tags?post=78"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}