{"id":72,"date":"2026-08-10T23:25:50","date_gmt":"2026-08-10T15:25:50","guid":{"rendered":"http:\/\/8.148.6.209\/?p=72"},"modified":"2026-08-10T23:29:06","modified_gmt":"2026-08-10T15:29:06","slug":"mysql","status":"publish","type":"post","link":"https:\/\/www.rainyblue.cn\/index.php\/2026\/08\/10\/mysql\/","title":{"rendered":"Mysql"},"content":{"rendered":"\n<h1 class=\"wp-block-heading\">MySQL\u901f\u6210<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">MySQL-Shell\u7684\u4f7f\u7528<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u542f\u52a8\u540e\u9ed8\u8ba4\u8fdb\u5165\\JS\u6a21\u5f0f\uff0c\u66f4\u9002\u5408\u6570\u636e\u5e93\u7ba1\u7406\u5458\u3001\u5f00\u53d1\u4eba\u5458\u7528\u4e8e\u81ea\u52a8\u5316\u8fd0\u7ef4\u3001\u96c6\u7fa4\u7ba1\u7406\u3001\u6570\u636e\u8fc1\u79fb\u7b49\u9ad8\u7ea7\u4efb\u52a1<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u652f\u6301JS\u3001Python\u3001SQL\u4e09\u79cd\u8bed\u8a00<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u9ed8\u8ba4\u4f7f\u7528JS<\/li>\n\n\n\n<li>\u4f7f\u7528\\+\u8bed\u8a00\u7f29\u5199\u6765\u5207\u6362\u8bed\u8a00\uff0c\u4ece\u800c\u6267\u884c\u8be5\u8bed\u8a00\u7684\u4ee3\u7801\n<ul class=\"wp-block-list\">\n<li>\\js<\/li>\n\n\n\n<li>\\py<\/li>\n\n\n\n<li>\\sql \u5207\u6362\u6210\u529f\u5373\u53ef\u6267\u884csql\u8bed\u53e5\uff0c\u4e0e\u5728\u7ec8\u7aef\u6216Navicat\u4e2d\u6267\u884c\u6548\u679c\u4e00\u81f4<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u5b98\u65b9\u63d0\u4f9b\u7684VSCode\u7684MySQL-Shell\u63d2\u4ef6\uff1aMySQL Shell for VS Code,\u7528ctrl+enter\u8fd0\u884c<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4ee5\u4e0b\u662f\u4e00\u4e9b\u7b80\u5355\u547d\u4ee4\uff1a<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u67e5\u8be2\u4fe1\u606f \\help<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fde\u63a5\u5230MySQL\u6570\u636e\u5e93 \\connect<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fde\u63a5\u672c\u5730MySQL\u670d\u52a1\u5668 \\connect root@localhost<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u521b\u5efa\u6570\u636e\u5e93 create database \u5e93\u540d;<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u9009\u62e9\u6570\u636e\u5e93 \\use \u5e93\u540d<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">SQL\u57fa\u7840<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">\u6570\u636e\u5e93\u7ba1\u7406\u7cfb\u7edf\u5206\u7c7b<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u5173\u7cfb\u578b\u6570\u636e\u5e93\u7ba1\u7406\u7cfb\u7edfROBMS<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u91c7\u7528\u5173\u7cfb\u6a21\u578b\u7ec4\u7ec7\u6570\u636e\uff0c\u901a\u8fc7\u4e8c\u7ef4\u8868\u8868\u793a\u6570\u636e\u4e4b\u95f4\u7684\u8054\u7cfb<\/li>\n\n\n\n<li>\u6570\u636e\u4e00\u822c\u90fd\u662f\u7528\u8868\u7684\u5f62\u5f0f\u6765\u5b58\u50a8\uff0cSQL\u7528\u6765\u64cd\u4f5c\u8868\u4e2d\u6570\u636e<\/li>\n\n\n\n<li>\u4e8c\u7ef4\u8868\u6bcf\u4e00\u884c\u8868\u793a\u4e00\u6761\u6570\u636e\u8bb0\u5f55<\/li>\n\n\n\n<li>\u4e8c\u7ef4\u8868\u6bcf\u4e00\u5217\u8868\u793a\u4e00\u4e2a\u5b57\u6bb5<\/li>\n\n\n\n<li>\u4e0d\u540c\u8868\u901a\u8fc7\u5173\u8054\u5b57\u6bb5\u6765\u5efa\u7acb\u8054\u7cfb<\/li>\n\n\n\n<li>\u5e38\u89c1\u4ee3\u8868\uff1aMySQL\u3001ORACLE\u3001PostgreSQL<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u975e\u5173\u7cfb\u578b\u6570\u636e\u5e93\u7ba1\u7406\u7cfb\u7edfNON-ROBMS<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u9488\u5bf9\u6570\u636e\u91cf\u5927\u3001\u6570\u636e\u7ed3\u6784\u590d\u6742\u3001\u6570\u636e\u7c7b\u578b\u591a\u6837\u7684\u6570\u636e\u5bf9ROBMS\u8fdb\u884c\u8865\u5145\u548c\u6269\u5c55\u800c\u6765<\/li>\n\n\n\n<li>\u5e38\u89c1\u4ee3\u8868\uff1aRedis\u3001mongoDB\u3001neo4j\u3001cassandra\u3001CouchDB<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">SQL\u5206\u7c7b<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u8bed\u53e5\u4e0d\u533a\u5206\u5927\u5c0f\u5199\uff0c\u4f46\u4e3a\u4e86\u63d0\u9ad8\u53ef\u8bfb\u6027\uff0c\u4f1a\u628a\u5173\u952e\u5b57\u5927\u5199\uff0c\u8868\u540d\u5217\u540d\u5176\u4ed6\u540d\u79f0\u5c0f\u5199<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u901a\u5e38\u628a <code>SQL<\/code> \u5206\u4e3a\u4e09\u7c7b\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>DDL (Data Definition Language): \u6570\u636e\u5b9a\u4e49\u8bed\u8a00\uff0c\u5982 CREATE\u3001DROP\u3001ALTER\u3001TRUNCATE<\/li>\n\n\n\n<li>DML (Data Manipulation Language): \u6570\u636e\u64cd\u4f5c\u8bed\u8a00\uff0c\u5982 INSERT\u3001UPDATE\u3001DELETE\u3001CALL\n<ul class=\"wp-block-list\">\n<li>\u7ec6\u5206\u8fd8\u53ef\u4ee5\u5206\u51fa\u4e00\u7c7b DQL (Data Query Language): \u6570\u636e\u67e5\u8be2\u8bed\u8a00\uff0c\u5982 SELECT<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>DCL (Data Contral Language): \u6570\u636e\u67e5\u8be2\u8bed\u8a00\uff0c\u5982 GRANT\u3001REVOKE<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">MySQL\u6570\u636e\u7c7b\u578b<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u6570\u503c\u7c7b\u578b\n<ul class=\"wp-block-list\">\n<li>\u6574\u6570\u7c7b\u578b\uff1aTINYINT\u3001SMALINT\u3001INT\u3001BIGINT(\u8303\u56f4\u5c0f\u2192\u5927)<\/li>\n\n\n\n<li>\u6d6e\u70b9\u6570\u7c7b\u578b\uff1aFLOAT\u3001DOUBLE\u3001DECIMAL(a,b) \u957f\u5ea6\u4e3aa\uff0c\u4fdd\u7559b\u4f4d\u5c0f\u6570<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>\u65e5\u671f\u548c\u65f6\u95f4\u7c7b\u578b\n<ul class=\"wp-block-list\">\n<li>DATE\uff1a\u4ec5\u5b58\u50a8\u65e5\u671f\uff0c\u683c\u5f0f\u4e3aYYYY-MM-DD<\/li>\n\n\n\n<li>TIME\uff1a\u4ec5\u5b58\u50a8\u65f6\u95f4\uff0c\u683c\u5f0f\u4e3aHH:MM:SS<\/li>\n\n\n\n<li>DATETIME\uff1a\u5b58\u50a8\u5b8c\u6574\u7684\u65e5\u671f\u548c\u65f6\u95f4<\/li>\n\n\n\n<li>TIMESTAMP\uff1a\u5b58\u50a8\u65f6\u95f4\u6233<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>\u5b57\u7b26\u4e32\u7c7b\u578b\n<ul class=\"wp-block-list\">\n<li>\u5b9a\u957f\u5b57\u7b26\u4e32\uff1aCHAR(n) \u5b9e\u9645\u5360\u7528\u5b57\u8282\u53ea\u53d6\u51b3\u4e8en\uff0c\u65e0\u8bba\u662f\u5426\u5b58\u6ee1\u90fd\u4e00\u5b9a\u4e3an<\/li>\n\n\n\n<li>\u53d8\u957f\u5b57\u7b26\u4e32\uff1aVARCHAR(n) \u5b9e\u9645\u5360\u7528\u5b57\u8282\u53d6\u51b3\u4e8e\u5b57\u7b26\uff0c\u6700\u5927\u4e3an<\/li>\n\n\n\n<li>TEXT\/BLOB: \u7528\u4e8e\u5b58\u50a8\u5927\u6bb5\u6587\u672c\u6216\u4e8c\u8fdb\u5236\u6570\u636e\uff08\u5982\u6587\u7ae0\u3001\u56fe\u7247\uff09\uff0c\u4e0d\u5efa\u8bae\u7528\u4e8e\u9891\u7e41\u67e5\u8be2\u7684\u5b57\u6bb5<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>JSON\u7c7b\u578b\n<ul class=\"wp-block-list\">\n<li>JSON\uff1a\u539f\u751f\u652f\u6301JSOM\u683c\u5f0f\u6570\u636e\u5b58\u50a8\uff0c\u9002\u5408\u7075\u6d3b\u7ed3\u6784\u6570\u636e\uff0c\u5982\u7528\u6237\u914d\u7f6e\u3001\u65e5\u5fd7\u4fe1\u606f<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>\u7a7a\u95f4\u7c7b\u578b\n<ul class=\"wp-block-list\">\n<li>POINT(\u70b9)<\/li>\n\n\n\n<li>LINESTRING(\u7ebf)<\/li>\n\n\n\n<li>POLYGON(\u591a\u8fb9\u5f62)<\/li>\n\n\n\n<li>GEOMETRY\uff1a\u901a\u7528\u57fa\u7840\u7c7b\u578b<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>\u96c6\u5408\u7c7b\u578b\n<ul class=\"wp-block-list\">\n<li>SET\uff1a\u5982SET(\u2019\u9605\u8bfb\u2018,&#8217;\u8fd0\u52a8&#8217;,&#8217;\u97f3\u4e50&#8217;)\uff0c\u9002\u5408\u591a\u9009\u6807\u7b7e<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">SQL\u5e38\u7528\u547d\u4ee4<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728MySQL\u547d\u4ee4\u884c\u5ba2\u6237\u7aef\u6216\u8005GUI\u5de5\u5177\u4e2d\u6267\u884c\u547d\u4ee4\uff0c\u547d\u4ee4\u7ed3\u5c3e\u8bb0\u5f97\u5e26\u5206\u53f7<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u547d\u4ee4\u884c\u5ba2\u6237\u7aef:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>MySQL 8.0 Command Line Client\uff08\u4ec5\u652f\u6301SQL\uff09<\/li>\n\n\n\n<li>MySQL Shell\uff08\u652f\u6301sql\u3001js\u3001py\uff0c\u9ed8\u8ba4js\uff0c\u4f7f\u7528\u524d\u8bb0\u5f97\u6267\u884c\\sql\u5207\u6362\uff09<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">\u67e5\u770b\u5f53\u524d\u5b58\u5728\u7684\u6570\u636e\u5e93<\/h3>\n\n\n\n<pre class=\"wp-block-preformatted\">&nbsp;show databases;<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u521b\u5efa\u6570\u636e\u5e93<\/h3>\n\n\n\n<pre class=\"wp-block-preformatted\">&nbsp;create \u6570\u636e\u5e93\u540d\u5b57;<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u5220\u9664\u6570\u636e\u5e93<\/h3>\n\n\n\n<pre class=\"wp-block-preformatted\">&nbsp;drop database \u6570\u636e\u5e93\u540d\u5b57;<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u9009\u62e9\u6570\u636e\u5e93<\/h3>\n\n\n\n<pre class=\"wp-block-preformatted\">&nbsp;\/\/\u521b\u5efa\u8868\u4e4b\u524d\u9700\u8981\u9009\u62e9\u6570\u636e\u5e93\uff0c\u518d\u5728\u6570\u636e\u5e93\u5185\u521b\u5efa\u8868<br>&nbsp;use game;<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u521b\u5efa\u8868<\/h3>\n\n\n\n<pre class=\"wp-block-preformatted\"><code>\u00a0create table \u8868\u540d(\u5b57\u6bb5\u540d\u79f0 \u6570\u636e\u7c7b\u578b\uff0c\u5b57\u6bb5\u540d\u79f0 \u6570\u636e\u7c7b\u578b)<br>\u00a0\u200b<br>\u00a0create table player(<br>\u00a0    id INT,<br>\u00a0 \u00a0  name VARCHAR(100),<br>\u00a0 \u00a0 \u00a0level INT,<br>\u00a0 \u00a0  exp INT,<br>\u00a0 \u00a0  gold DECIMAL(10,2)<br>\u00a0);<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u67e5\u770b\u8868\u7684\u7ed3\u6784<\/h3>\n\n\n\n<pre class=\"wp-block-preformatted\">&nbsp;DESC \u8868\u540d;<br>&nbsp;-- \u4f1a\u663e\u793a\u6bcf\u5217\u540d\u79f0\u3001\u6570\u636e\u7c7b\u578b\u3001\u662f\u5426\u5141\u8bb8\u4e3a\u7a7a\u3001\u9ed8\u8ba4\u503c\u7b49\u7b49<\/pre>\n\n\n\n<figure class=\"wp-block-image\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/8.148.6.209\/wp-content\/uploads\/2026\/08\/image-20260713212548410.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"747\" height=\"296\" data-original=\"http:\/\/8.148.6.209\/wp-content\/uploads\/2026\/08\/image-20260713212548410.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"image-20260713212548410\" class=\"wp-image-75\"  sizes=\"auto, (max-width: 747px) 100vw, 747px\" \/><\/div><\/figure>\n\n\n\n<h3 class=\"wp-block-heading\">\u4fee\u6539\u8868\u7ed3\u6784<\/h3>\n\n\n\n<pre class=\"wp-block-preformatted\">&nbsp;-- \u4fee\u6539\u5217\u7c7b\u578b\u957f\u5ea6 &nbsp;<br>&nbsp;-- \u5173\u952e\u5b57 &nbsp; &nbsp;  \u8868\u540d &nbsp; &nbsp;  \u5173\u952e\u5b57 &nbsp; &nbsp;  \u5217\u540d \u65b0\u7684\u6570\u636e\u7c7b\u578b<br>&nbsp;ALTER TABLE player MODIFY COLUMN name VARCHAR(200);-- \u540e\u9762\u518d\u8ddf\u4e0a\u6570\u636e\u8868\u793a\u521d\u59cb\u503c\u4e3a\u8be5\u6570\u636e<br>&nbsp;\u200b<br>&nbsp;-- \u4fee\u6539\u5b57\u6bb5\u540d<br>&nbsp;-- \u5173\u952e\u5b57 &nbsp; &nbsp;  \u8868\u540d &nbsp; &nbsp;  \u5173\u952e\u5b57 &nbsp; &nbsp;  \u5217\u540d \u5173\u952e\u5b57 \u65b0\u5217\u540d<br>&nbsp;ALTER TABLE player RENAME COLUMN name to nick_name;<br>&nbsp;\u200b<br>&nbsp;-- \u589e\u52a0\u65b0\u5b57\u6bb5\uff08\u5217\uff09<br>&nbsp;-- \u5173\u952e\u5b57 &nbsp; &nbsp;  \u8868\u540d &nbsp; &nbsp;  \u5173\u952e\u5b57 &nbsp;  \u65b0\u589e\u5b57\u6bb5\u540d  \u6570\u636e\u7c7b\u578b<br>&nbsp;ALTER TABLE player ADD COLUMN last_login DATETIME;<br>&nbsp;\u200b<br>&nbsp;-- \u5220\u67d0\u5217<br>&nbsp;-- \u5173\u952e\u5b57 &nbsp; &nbsp;  \u8868\u540d &nbsp; &nbsp;  \u5173\u952e\u5b57 &nbsp; &nbsp;  \u5f85\u5220\u5b57\u6bb5<br>&nbsp;ALTER TABLE player DROP COLUMN last_login;<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u5220\u9664\u8868<\/h3>\n\n\n\n<pre class=\"wp-block-preformatted\">&nbsp;-- \u5173\u952e\u5b57 &nbsp; &nbsp; \u8868\u540d<br>&nbsp;DROP TABLE player<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u8868\u4e2d\u6570\u636e\u7684\u589e\u5220\u6539\u67e5<\/h3>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h4 class=\"wp-block-heading\">\u589e\u52a0\u8868\u4e2d\u6570\u636e<\/h4>\n\n\n\n<pre class=\"wp-block-preformatted\">INSERT INTO player(id,name,level,exp,gold) VALUES (1,'\u5f20\u4e09',1,1,1);<br>INSERT INTO player(id,name,level,exp,gold) VALUES (1,'\u5f20\u4e09',1,1,1),(2\uff0c'\u674e\u56db'\uff0c2\uff0c2\uff0c2);<\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u5982\u679c<code>\u8868\u540d<\/code>\u540e\u9762\u7684\u5217\u540d\u548c\u8868\u7ed3\u6784\u5b8c\u5168\u4e00\u81f4 (\u987a\u5e8f\u4e5f\u4e00\u81f4)\uff0c\u5c31\u53ef\u4ee5\u7701\u7565\uff0c\u76f4\u63a5\u5199\u5173\u952e\u5b57 <code>VALUE<\/code>+ \u503c\uff0c\u6ce8\u610f\u53ef\u4ee5\u540c\u65f6\u63d2\u5165\u591a\u6761\u6570\u636e\uff0c\u9017\u53f7\u5206\u9694\u5373\u53ef\u3002\u5982\u4e0b<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">INSERT INTO player VALUES (1,'\u5f20\u4e09',1,1,1);<\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e5f\u53ef\u4ee5\u53ea\u5199\u51fa\u90e8\u5206\u5217\u540d\u79f0\uff0c\u76f8\u5e94\u7684\u540e\u9762\u7684\u503c\u4e5f\u53ea\u5199\u90e8\u5206\uff0c\u8fd9\u6837\u5176\u4ed6\u503c\u5c31\u4f1a\u4f7f\u7528\u521b\u5efa\u8868\u65f6\u8bbe\u5b9a\u7684\u9ed8\u8ba4\u503c\u6765\u586b\u5145\uff0c\u4e0d\u8bbe\u7f6e\u5c31\u662f<code>\u7a7a\u503c<\/code>\u3002\u5982\u4e0b<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">INSERT INTO player(name,gold) VALUES ('\u5f20\u4e09',1);<\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h4 class=\"wp-block-heading\">\u67e5\u770b\u8868\u4e2d\u6570\u636e<\/h4>\n\n\n\n<pre class=\"wp-block-preformatted\">SELECT * FROM player;<br>SELECT id,name FROM player;<\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u6ce8\u610f * \u4ee3\u8868\u6240\u6709\u5217\uff0c\u5982\u679c\u4e0d\u60f3\u8981\u6240\u6709\u5217\uff0c\u5c31\u9010\u4e00\u679a\u4e3e\uff0c\u9017\u53f7\u5206\u9694\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h4 class=\"wp-block-heading\">\u8868\u4e2d\u6570\u636e\u9ed8\u8ba4\u503c<\/h4>\n\n\n\n<pre class=\"wp-block-preformatted\">ALTER TABLE player MODIFY level INT DEFAULT 1;<\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fd9\u91cc\u6dfb\u52a0\u9ed8\u8ba4\u503c\u4e4b\u540e\u5c31\u53d1\u73b0\u7701\u7565\u8f93\u5165\u9ed8\u8ba4\u503c\u4e0d\u518d\u4e3a <code>Null<\/code>\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h4 class=\"wp-block-heading\">\u4fee\u6539\u8868\u4e2d\u6570\u636e<\/h4>\n\n\n\n<pre class=\"wp-block-preformatted\">-- \u5173\u952e\u5b57 \u8868\u540d \u5173\u952e\u5b57 \u5217\u540d   \u6539\u503c \u5173\u952e\u5b57 \u5217\u540d     \u4eba\u540d<br>UPDATE player set level = 1 where name = '\u674e\u56db';<\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u4fee\u6539\u6240\u6709\u73a9\u5bb6\u7684\u6570\u636e\uff0c\u591a\u4e2a\u5b57\u6bb5\u7528\u9017\u53f7\u9694\u5f00\uff0c\u5982\u4e0b<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">UPDATE player set exp=0,gold=0;<\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h4 class=\"wp-block-heading\">\u5220\u9664\u8868\u4e2d\u6570\u636e<\/h4>\n\n\n\n<pre class=\"wp-block-preformatted\">DELETE FROM player WHERE gold = 0;<\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">\u6570\u636e\u7684\u5bfc\u5165\u5bfc\u51fa<\/h2>\n\n\n\n<h2 class=\"wp-block-heading\">\u5e38\u7528\u8bed\u53e5<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">where\u5b50\u53e5<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u7528\u6765\u63d0\u53d6\u6ee1\u8db3\u6307\u5b9a\u6807\u51c6\u7684\u8bb0\u5f55<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5173\u952e\u5b57\u4e3awhere\uff0c\u540e\u63a5\u9700\u8981\u7b5b\u9009\u7684\u5b57\u6bb5<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">-- 1. \u67e5\u8be2\u7b49\u7ea7\u5927\u4e8e 1 \u7684\u6240\u6709\u73a9\u5bb6\u4fe1\u606f<br>SELECT * FROM player WHERE level &gt; 1;<br><br>-- 2. \u591a\u6761\u4ef6\u7b5b\u9009 (AND)\uff1a\u67e5\u8be2\u7b49\u7ea7\u5728 1 \u5230 5 \u4e4b\u95f4\u7684\u73a9\u5bb6<br>SELECT * FROM player WHERE level &gt; 1 AND level &lt; 5;<br><br>-- 3. \u903b\u8f91\u7ec4\u5408 (AND\/OR\/\u62ec\u53f7)\uff1a<br>--    \u540c\u65f6\u6ee1\u8db3\u4ee5\u4e0b\u4e09\u4e2a\u6761\u4ef6\uff1a<br>--    a) \u7b49\u7ea7\u5fc5\u987b\u5927\u4e8e 1<br>--    b) \u7ecf\u9a8c\u503c\u5fc5\u987b\u5c0f\u4e8e 5<br>--    c) \u5e76\u4e14\uff08\u7b49\u7ea7\u5c0f\u4e8e 5 \u6216\u8005 \u7ecf\u9a8c\u503c\u5927\u4e8e 1\uff09\u2014\u2014 \u53ea\u8981\u62ec\u53f7\u5185\u4efb\u4e00\u6761\u4ef6\u6210\u7acb\u5373\u53ef<br>SELECT * FROM player WHERE level &gt; 1 AND (level &lt; 5 OR exp &gt; 1) AND exp &lt; 5;<br><br>-- 4. \u591a\u503c\u67e5\u8be2 (IN)\uff1a\u67e5\u8be2\u7b49\u7ea7\u6070\u597d\u4e3a 1\u30013 \u6216 5 \u7684\u73a9\u5bb6\uff08\u7b49\u540c\u4e8e level=1 OR level=3 OR level=5\uff09<br>SELECT * FROM player WHERE level IN (1,3,5);<br><br>-- 5.\u533a\u95f4\u67e5\u8be2\uff08between...and...\uff09\uff1a\u67e5\u8be21\u523010\u4e4b\u95f4\u7684\u6570\u636e<br>SELECT *FROM player WHERE level BETWEEN 1 AND 10;<br><br>-- 6.\u53d6\u53cd\uff08NOT\uff09\uff1a\u52a0\u5728\u5404\u79cd\u6761\u4ef6\u8bed\u53e5\u6216\u6bd4\u8f83\u8fd0\u7b97\u7b26\u524d\u9762<br>SELECT *FROM player WHERE level NOT BETWEEN 1 AND 10;<br><br>-- 7.\u6a21\u7cca\u67e5\u8be2\uff08LIKE\uff09\uff1a\u540e\u9762\u52a0\u4e0a\u7528\u6765\u5339\u914d\u7684\u6a21\u5f0f\uff0c\u4f7f\u7528\u4ee5\u4e0b\u4e8c\u79cd\u901a\u914d\u7b26<br>--   %       \u96f6\u4e2a\u6216\u591a\u4e2a\u4efb\u610f\u5b57\u7b26<br>--   _       \u4e00\u4e2a\u4efb\u610f\u5b57\u7b26<br>-- \u67e5\u627e\u59d3\u738b\u7684\u73a9\u5bb6<br>SELECT *FROM player WHERE name LIKE '\u738b%'<br>-- \u67e5\u627e\u540d\u5b57\u5305\u542b\u738b\u7684\u73a9\u5bb6<br>SELECT *FROM player WHERE name LIKE '%\u738b%'<br>-- \u67e5\u627e\u59d3\u738b\u7684\u4e8c\u5b57\u73a9\u5bb6<br>SELECT *FROM player WHERE name LIKE '\u738b_'<br><br>-- 8.\u6b63\u5219\u8868\u8fbe\u5f0f\uff08REGEXP\/regexp\uff09<br>-- Tips: \u5e38\u7528\u901a\u914d\u7b26<br>-- .       : \u5339\u914d\u4efb\u610f\u4e00\u4e2a\u5b57\u7b26<br>-- ^       : \u5339\u914d\u5b57\u7b26\u4e32\u7684\u5f00\u5934<br>-- $       : \u5339\u914d\u5b57\u7b26\u4e32\u7684\u7ed3\u5c3e<br>-- [abc]   : \u5339\u914d\u65b9\u62ec\u53f7\u5185\u5217\u51fa\u7684\u4efb\u610f\u4e00\u4e2a\u5b57\u7b26 (\u4f8b\u5982 a, b \u6216 c)<br>-- [a-z]   : \u5339\u914d\u6307\u5b9a\u8303\u56f4\u5185\u7684\u4efb\u610f\u4e00\u4e2a\u5b57\u7b26 (\u4f8b\u5982\u5c0f\u5199\u5b57\u6bcd a \u5230 z\u6216\u8005\u6570\u5b571\u52309)<br>-- A|B     : \u5339\u914d A \u6216\u8005 B (\u903b\u8f91\u201c\u6216\u201d)<br>-- \u67e5\u627e\u59d3\u738b\u7684\u73a9\u5bb6<br>SELECT *FROM player WHERE name REGEXP '^\u738b';<br>-- \u67e5\u627e\u540d\u5b57\u4ee5\u738b\u7ed3\u5c3e\u7684\u73a9\u5bb6<br>SELECT *FROM player WHERE name REGEXP '\u738b$';<br>-- \u67e5\u627e\u59d3\u738b\u7684\u4e8c\u5b57\u73a9\u5bb6<br>SELECT *FROM player WHERE name REGEXP '^\u738b.$';<br>-- \u67e5\u627e\u540d\u5b57\u5305\u542b\u738b\u7684\u73a9\u5bb6<br>SELECT *FROM player WHERE name REGEXP '\u738b';<br>-- \u67e5\u627e\u540d\u5b57\u5305\u542b\u738b\u6216\u8005\u5f20\u7684\u73a9\u5bb6<br>SELECT *FROM player WHERE name REGEXP '[\u738b\u5f20]';<br>SELECT *FROM player WHERE name REGEXP '\u738b|\u5f20';<br>-- \u7ec3\u4e60<br>-- \u67e5\u627e\u90ae\u4ef6\u5730\u5740\u4ee5 \"zhangsan\" \u5f00\u5934\u7684\u73a9\u5bb6<br>SELECT * FROM player WHERE email REGEXP '^zhangsan'; <br>SELECT * FROM player WHERE email LIKE 'zhangsan%';  <br>-- \u67e5\u627e\u90ae\u4ef6\u5730\u5740\u4ee5 a\u3001b \u6216 c \u5f00\u5934\u7684\u73a9\u5bb6<br>SELECT * FROM player WHERE email REGEXP '^[abc]';   <br>SELECT * FROM player WHERE email REGEXP '^[a-c]';   <br>-- \u67e5\u627e\u90ae\u4ef6\u5730\u5740\u4ee5 \"net\" \u7ed3\u5c3e\u7684\u73a9\u5bb6<br>SELECT * FROM player WHERE email REGEXP 'net$';      <br>SELECT * FROM player WHERE email LIKE '%net';   <br><br>-- 9.\u67e5\u627e\u7a7a\u503c\/\u975e\u7a7a\u503c\uff08is NULL\/is NOT NULL\uff09<br>-- \u6216\u8005\u4f7f\u7528NULL\u6bd4\u8f83\u64cd\u4f5c\u7b26  &lt;=&gt;NULL<br>-- \u67e5\u627e\u90ae\u7bb1\u4e3a\u7a7a\u7684\u73a9\u5bb6<br>SELECT * FROM player WHERE email is NULL;<br>SELECT * FROM player WHERE email &lt;=&gt; NULL;<br>-- \u7a7a\u5b57\u7b26\u4e32\u548cNULL\u4e0d\u4e00\u6837\uff0c\u524d\u8005\u7528=\u6765\u5224\u65ad,\u5982\u4e0b<br>SELECT * FROM player WHERE email = '';<\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u903b\u8f91\u8fd0\u7b97\u7b26\u4f18\u5148\u7ea7\u987a\u5e8f\uff1aNOT&gt;AND&gt;OR<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u6392\u5e8fORDER BY<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u6392\u5e8f\uff1a\u5173\u952e\u5b57order by\uff0c\u5bf9\u67e5\u8be2\u7ed3\u679c\u8fdb\u884c\u6392\u5e8f<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">-- 1.\u9ed8\u8ba4\u5347\u5e8f<br>SELECT * FROM player ORDER BY level;<br>-- 2.\u5b57\u6bb5\u540e\u52a0DESC\u5219\u964d\u5e8f<br>SELECT * FROM player ORDER BY level DESC;<br>-- 3.\u591a\u6761\u4ef6\u6392\u5e8f  \u6309\u7b49\u7ea7\u964d\u5e8f\u7684\u524d\u63d0\u4e0b\u518d\u6309\u7167\u7ecf\u9a8c\u503c\u5347\u5e8f\uff0c\u9ed8\u8ba4\u6216\u8005\u5b57\u6bb5\u540e\u52a0ASC\u8868\u793a\u5347\u5e8f<br>SELECT * FROM player ORDER BY level DESC,exp;<br>SELECT * FROM player ORDER BY level DESC,exp ASC;<br>-- 4.\u4f7f\u7528\u5217\u7684\u5e8f\u53f7\u6392\u5e8f  level\u5b57\u6bb5\u5728\u7b2c\u4e94\u5217\u65f6<br>SELECT * FROM player ORDER BY 5 DESC,exp;<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u805a\u5408\u51fd\u6570<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u7528\u6765\u5bf9\u67d0\u5217\u8fdb\u884c\u4e00\u4e9b\u8ba1\u7b97<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">-- Tips: \u5e38\u7528\u805a\u5408\u51fd\u6570<br>-- 1.AVG()   : \u8fd4\u56de\u96c6\u5408\u7684\u5e73\u5747\u503c<br>-- \u8fd4\u56de\u6240\u6709\u73a9\u5bb6\u7684\u7b49\u7ea7\u5e73\u5747\u503c<br>SELECT AVG(level) FROM player;<br><br>-- 2.COUNT() : \u8fd4\u56de\u96c6\u5408\u4e2d\u7684\u9879\u76ee\u6570\uff08\u8bb0\u5f55\u884c\u6570\uff09<br>-- \u6c42\u6240\u6709\u73a9\u5bb6\u603b\u4eba\u6570<br>SELECT COUNT(*) FROM player;<br><br>-- 3.MAX()   : \u8fd4\u56de\u6700\u5927\u503c<br>SELECT MAX(level) FROM player;<br>-- 4.MIN()   : \u8fd4\u56de\u6700\u5c0f\u503c<br>SELECT MIN(level) FROM player;<br>-- 5.SUM()   : \u6c42\u548c<br>SELECT SUM(exp) FROM player;<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u5206\u7ec4group by<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u7528\u4e8e\u5c06\u67e5\u8be2\u7ed3\u679c\u6309\u4e00\u4e2a\u6216\u591a\u4e2a\u5217\u8fdb\u884c\u5206\u7ec4\u7684\u5b50\u53e5\uff0c\u5e38\u4e0e\u805a\u5408\u51fd\u6570\u914d\u5408\u4f7f\u7528\uff0c\u5b9e\u73b0\u5bf9\u6bcf\u7ec4\u6570&#8211; \u636e\u7684\u7edf\u8ba1\u6c47\u603b\u3002<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">-- \u5206\u7ec4\u524d<br>SELECT COUNT(*) FROM player;<br>-- \u5206\u7ec4\u540e\uff1a\u6309 level\uff08\u7b49\u7ea7\uff09\u628a\u73a9\u5bb6\u5206\u6210\u4e0d\u540c\u7684\u7ec4\uff0c\u7136\u540e\u6570\u4e00\u6570\u6bcf\u7ec4\u91cc\u6709\u591a\u5c11\u4eba\u3002<br>SELECT level, COUNT(*) FROM player GROUP BY level;<br>SELECT level, COUNT(level) FROM player GROUP BY level;<\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">count()\u548ccount(level)\u533a\u522b\uff1a\u540e\u8005\u4e0d\u8ba1\u7b97level\u7684null\u6570 count() \u4e0d\u5173\u6ce8\u4efb\u4f55\u5217\u7684\u5177\u4f53\u503c\uff0c\u5305\u62ec NULL count(level) \u4f1a\u5ffd\u7565 level\u4e3a NULL \u7684\u884c<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u5206\u7ec4\u540e\u7b5b\u9009having<\/h3>\n\n\n\n<pre class=\"wp-block-preformatted\">-- \u6309 level\uff08\u7b49\u7ea7\uff09\u628a\u73a9\u5bb6\u5206\u6210\u4e0d\u540c\u7684\u7ec4\uff0c\u7136\u540e\u6570\u7b49\u7ea7\u5927\u4e8e4\u7684\u6bcf\u7ec4\u91cc\u6709\u591a\u5c11\u4eba\u3002<br>SELECT level, COUNT(level) FROM player GROUP BY level HAVING count(level)&gt;4;<br>-- \u6309 level\uff08\u7b49\u7ea7\uff09\u628a\u73a9\u5bb6\u5206\u6210\u4e0d\u540c\u7684\u7ec4\uff0c\u7136\u540e\u6570\u7b49\u7ea7\u5927\u4e8e4\u7684\u6bcf\u7ec4\u91cc\u6709\u591a\u5c11\u4eba\u5e76\u964d\u5e8f<br>SELECT level, COUNT(level) FROM player GROUP BY level HAVING count(level)&gt;4 ORDER BY count(level) DESC;<\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>MySQL\u901f\u6210 MySQL-Shell\u7684\u4f7f\u7528 \u542f\u52a8\u540e\u9ed8\u8ba4\u8fdb\u5165\\JS\u6a21\u5f0f\uff0c\u66f4\u9002\u5408\u6570\u636e\u5e93\u7ba1\u7406\u5458\u3001\u5f00\u53d1\u4eba\u5458\u7528\u4e8e\u81ea\u52a8\u5316 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":77,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-72","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/www.rainyblue.cn\/index.php\/wp-json\/wp\/v2\/posts\/72","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.rainyblue.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.rainyblue.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.rainyblue.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.rainyblue.cn\/index.php\/wp-json\/wp\/v2\/comments?post=72"}],"version-history":[{"count":3,"href":"https:\/\/www.rainyblue.cn\/index.php\/wp-json\/wp\/v2\/posts\/72\/revisions"}],"predecessor-version":[{"id":76,"href":"https:\/\/www.rainyblue.cn\/index.php\/wp-json\/wp\/v2\/posts\/72\/revisions\/76"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.rainyblue.cn\/index.php\/wp-json\/wp\/v2\/media\/77"}],"wp:attachment":[{"href":"https:\/\/www.rainyblue.cn\/index.php\/wp-json\/wp\/v2\/media?parent=72"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.rainyblue.cn\/index.php\/wp-json\/wp\/v2\/categories?post=72"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.rainyblue.cn\/index.php\/wp-json\/wp\/v2\/tags?post=72"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}