{"id":33,"date":"2025-11-07T20:44:09","date_gmt":"2025-11-07T12:44:09","guid":{"rendered":"http:\/\/101.132.157.20\/?p=33"},"modified":"2025-11-07T20:53:41","modified_gmt":"2025-11-07T12:53:41","slug":"sql%e6%9f%a5%e8%af%a2%e8%af%ad%e5%8f%a5%e5%9f%ba%e7%a1%80%e7%af%87","status":"publish","type":"post","link":"https:\/\/www.tangent0712.top\/index.php\/2025\/11\/07\/sql%e6%9f%a5%e8%af%a2%e8%af%ad%e5%8f%a5%e5%9f%ba%e7%a1%80%e7%af%87\/","title":{"rendered":"SQL\u67e5\u8be2\u8bed\u53e5(\u57fa\u7840\u7bc7)"},"content":{"rendered":"<p id=\"20251107182849-rl29i6m\">SQL\u662f\u4e00\u95e8\u8f83\u4e3a\u901a\u7528\u7684\u7528\u6765\u64cd\u4f5c\u6570\u636e\u5e93\u7684\u8bed\u8a00,\u662f\u7528\u4e8e\u8bbf\u95ee\u548c\u5904\u7406\u6570\u636e\u5e93\u7684\u6807\u51c6\u7684\u8ba1\u7b97\u673a\u8bed\u8a00.<\/p>\n<p id=\"20251107183200-x8gz9kz\">\u6570\u636e\u5e93\u7ba1\u7406\u7cfb\u7edf\u53ef\u4ee5\u64cd\u4f5c\u6570\u636e\u5e93,\u5bf9\u5916\u66b4\u9732\u7684\u63a5\u53e3\u5927\u591a\u662f\u652f\u6301SQL\u8bed\u8a00\u7684.<\/p>\n<p id=\"20251107183349-7tkcyht\">SQL\u8bed\u53e5\u5206\u4e3a\u4e24\u90e8\u5206:<\/p>\n<ul id=\"20251107183426-42b3xlt\" class=\"wp-block-list\">\n<li>\u6570\u636e\u67e5\u8be2\u8bed\u8a00(DQL: Data Query Language)<\/li>\n\n<li>\u6570\u636e\u64cd\u7eb5\u8bed\u8a00(DML\uff1aData Manipulation Language)<\/li>\n<\/ul>\n<p id=\"20251107183439-yzs8o1n\">\u5173\u7cfb\u578b\u6570\u636e\u5e93\u5305\u62ec\u591a\u5f20\u8868\u548c\u8868\u4e4b\u95f4\u7684\u5173\u7cfb.<\/p>\n<h3 class=\"wp-block-heading\" id=\"CREATE-DATABASE-\u521b\u5efa\u6570\u636e\u5e93\">CREATE DATABASE \u521b\u5efa\u6570\u636e\u5e93<\/h3>\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p id=\"20251107200746-v0fyqhh\">\u6ce8\u610f:SQL\u8bed\u53e5\u7684\u5173\u952e\u5b57\u4e2d\u7684\u5927\u5c0f\u5199\u662f\u4e0d\u654f\u611f\u7684<\/p>\n<\/blockquote>\n<pre class=\"wp-block-code\"><code>CREATE DATABASE dbname;\n<\/code><\/pre>\n<p id=\"20251107200117-4xa4asu\">\u793a\u4f8b:<\/p>\n<pre class=\"wp-block-code\"><code>CREATE DATABASE test;\n<\/code><\/pre>\n<h3 class=\"wp-block-heading\" id=\"CREATE-TABLE-\u521b\u5efa\u8868\">CREATE TABLE \u521b\u5efa\u8868<\/h3>\n<pre class=\"wp-block-code\"><code>CREATE TABLE table_name(\n    column_name1 data_type(size),\n    column_name2 data_type(size),\n    column_name3 data_type(size),\n    ....\n)\n<\/code><\/pre>\n<ul id=\"20251107183912-wy2nzhv\" class=\"wp-block-list\">\n<li>table_name\u548ccolumn_name\u4e0d\u9700\u8981\u7528\u5f15\u53f7\u5305\u56f4<\/li>\n\n<li>data_type(size)\u7684\u5e38\u7528\u7c7b\u578b\u6709:<\/li>\n<\/ul>\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>\u6570\u636e\u7c7b\u578b<\/th>\n<th>\u8bf4\u660e<\/th><\/tr><\/thead>\n<tbody><tr><td>INT(size)<\/td>\n<td>\u5b58\u50a8intage\u53d8\u91cf,size\u662f\u6700\u5927\u4f4d\u6570,\u9ed8\u8ba4\u4e3a11<\/td><\/tr>\n<tr><td>DECIMAL(size,d)<\/td>\n<td>\u5b58\u50a8double\u53d8\u91cf,\u5141\u8bb8\u56fa\u5b9a\u7684\u5c0f\u6570\u70b9,size\u89c4\u5b9a\u6574\u6570\u7684\u6700\u5927\u4f4d\u6570,d\u8868\u793a\u5c0f\u6570\u70b9\u53f3\u8fb9\u7684\u6700\u5927\u4f4d\u6570<\/td><\/tr>\n<tr><td>CHAR(size)<\/td>\n<td>\u5b58\u50a8\u56fa\u5b9a\u957f\u5ea6\u7684String,size\u6307\u5b9aString\u7684\u957f\u5ea6<\/td><\/tr>\n<tr><td>VARCHAR(size)<\/td>\n<td>\u5b58\u50a8\u53ef\u53d8\u957f\u5ea6\u7684String,size\u6307\u5b9aString\u7684\u6700\u5927\u957f\u5ea6<\/td><\/tr>\n<tr><td>DATETIME()<\/td>\n<td>\u5b58\u50a8\u65e5\u671f\u548c\u65f6\u95f4,\u683c\u5f0f\u4e3aYYYY-MM-DD HH:MM:SS<\/td><\/tr><\/tbody><\/table><\/figure>\n<p id=\"20251107184149-z32xhr8\">\u793a\u4f8b:<\/p>\n<pre class=\"wp-block-code\"><code>CREATE TABLE Persons(\n    PersonID int,\n    LastName varchar(255),\n    FirstName varchar(255),\n    Address varchar(255),\n    City varchar(255),\n);\n<\/code><\/pre>\n<h3 class=\"wp-block-heading\" id=\"INSERT-INTO-\u63d2\u5165\u6570\u636e\">INSERT INTO \u63d2\u5165\u6570\u636e<\/h3>\n<pre class=\"wp-block-code\"><code>INSERT INTO table_name (\n    column_name1, \n    column_name2,\n    ...\n) VALUES (\n    value1, \n    value2,\n    ....\n);\n<\/code><\/pre>\n<p id=\"20251107200426-u7v8xkf\">\u793a\u4f8b:<\/p>\n<pre class=\"wp-block-code\"><code>INSERT INTO Persons (\n    LastName, \n    Address\n) VALUES (\n    'Wilson', \n    'Champs-Elysees'\n);\n\n<\/code><\/pre>\n<h3 class=\"wp-block-heading\" id=\"SELECT-\u67e5\u8be2\u6570\u636e\">SELECT \u67e5\u8be2\u6570\u636e<\/h3>\n<p id=\"20251107200542-w3l23dj\">SELECT\u8bed\u53e5\u4ece\u8868\u4e2d\u9009\u53d6\u6570\u636e,\u8fd4\u56de\u4e00\u5f20\u8868(\u88ab\u79f0\u4e3a\u7ed3\u679c\u96c6)<\/p>\n<pre class=\"wp-block-code\"><code>SELECT \n    column_name1,\n    column_name2,\n    ...\nFROM \n    table_name;\n<\/code><\/pre>\n<p id=\"20251107200823-r0end5i\">\u200b*\u200b\u901a\u914d\u7b26\u4ee3\u8868\u6240\u6709\u7684\u5217.<\/p>\n<p id=\"20251107200856-ht80ya4\">\u793a\u4f8b:<\/p>\n<pre class=\"wp-block-code\"><code>SELECT \n    *\nFROM \n    Persons;\n--\u8fd4\u56dePerson\u8868\u4e2d\u6240\u6709\u7684\u5b57\u6bb5\n<\/code><\/pre>\n<h3 class=\"wp-block-heading\" id=\"DISTINCT-\u53bb\u91cd\">DISTINCT \u53bb\u91cd<\/h3>\n<pre class=\"wp-block-code\"><code>SELECT DISTINCT \n    column_name \nFROM \n    table_name;\n<\/code><\/pre>\n<p id=\"20251107201744-cig7h4i\">\u6ce8\u610f:\u5982\u679c\u53ea\u67e5\u8be2\u4e00\u4e2a\u5b57\u6bb5,\u90a3\u4e48\u5f88\u663e\u7136distinct\u4f1a\u5bf9\u67e5\u8be2\u7684\u5b57\u6bb5\u8fdb\u884c\u53bb\u91cd,\u4f46\u5982\u679c\u67e5\u8be2\u7684\u662f\u591a\u4e2a\u5b57\u6bb5,\u4ffa\u4e48distinct\u53bb\u91cd\u7684\u5176\u5b9e\u662f\u591a\u4e2a\u5b57\u6bb5\u7684\u7ec4\u5408<\/p>\n<h3 class=\"wp-block-heading\" id=\"WHERE-\u6761\u4ef6\u8fc7\u6ee4\">WHERE \u6761\u4ef6\u8fc7\u6ee4<\/h3>\n<pre class=\"wp-block-code\"><code>SELECT \n    column_name \nFROM \n    table_name \nWHERE \n    Boolean;\n<\/code><\/pre>\n<p id=\"20251107202141-5m8dgp3\">\u5e03\u5c14\u8868\u8fbe\u5f0f\u4e2d\u53ef\u4ee5\u5305\u542bcolumn_name,\u53ea\u6709\u5f53\u8be5\u884c\u4f7fWHERE\u8bed\u53e5\u540e\u9762\u7684\u5e03\u5c14\u8868\u8fbe\u5f0f\u8fd4\u56detrue\u65f6,\u8be5\u884c\u624d\u4f1a\u88ab\u663e\u793a<\/p>\n<p id=\"20251107202507-251qcfn\">\u5e38\u89c1\u7684\u903b\u8f91\u8fd0\u7b97\u7b26\u6709=\u200b,\u200b(\u4e0d\u7b49\u4e8e),&gt;\u200b,=\u200b,&lt;=\u200b,BETWEEN\u200b,LIKE\u200b,\u5176\u4e2d,BETWEEN\u200b\u548cLIKE\u200b\u5c06\u5728\u540e\u9762\u7684\u8fdb\u9636\u6559\u7a0b\u8bf4\u660e<\/p>\n<p id=\"20251107202318-mh3wwz8\">\u9664\u6b64\u4e4b\u5916,\u8fd8\u53ef\u4ee5\u7528AND\u200b\u548cOR\u200b\u6765\u8fde\u63a5\u4e24\u4e2a\u5e03\u5c14\u8868\u8fbe\u5f0f,\u5e03\u5c14\u8868\u8fbe\u5f0f\u4e2d\u4e5f\u53ef\u4ee5\u7528\u5706\u62ec\u53f7\u6765\u786e\u5b9a\u8fd0\u7b97\u4f18\u5148\u7ea7<\/p>\n<h3 class=\"wp-block-heading\" id=\"ORDER-BY-\u6392\u5e8f\">ORDER BY \u6392\u5e8f<\/h3>\n<pre class=\"wp-block-code\"><code>SELECT \n    column_name\nFROM \n    table_name\nORDER BY\n    column_name1,\n    column_name2\n    ASC\/DESC\n<\/code><\/pre>\n<p id=\"20251107203036-onik0f8\">\u82e5\u8981\u6309\u7167\u5347\u5e8f\u6392\u5e8f,\u8bf7\u4f7f\u7528ASC\u200b,\u82e5\u8981\u6309\u7167\u964d\u5e8f\u6392\u5e8f,\u8bf7\u4f7f\u7528DESC\u200b<\/p>\n<p id=\"20251107203201-yazmefk\">\u5982\u679c\u5bf9\u591a\u4e2a\u5b57\u6bb5\u8fdb\u884c\u6392\u5e8f,\u90a3\u4e48\u6392\u5728\u524d\u9762\u7684\u5b57\u6bb5\u4f18\u5148\u7ea7\u66f4\u9ad8,\u4ee5\u4e0a,\u5148\u5bf9column_name1\u8fdb\u884c\u6392\u5e8f,\u7136\u540e\u5728column_name1\u7684\u5185\u90e8\u5bf9column_name2\u8fdb\u884c\u6392\u5e8f.<\/p>\n<h3 class=\"wp-block-heading\" id=\"UPDATE-\u66f4\u65b0\u6570\u636e\">UPDATE \u66f4\u65b0\u6570\u636e<\/h3>\n<pre class=\"wp-block-code\"><code>UPDATE \n    table_name\nSET \n    column1 = value1,\n    column2 = value2,\n    ...\nWHERE \n    Boolean;\n<\/code><\/pre>\n<p id=\"20251107203435-8m22dvg\">\u6ce8\u610f:\u4e0a\u9762\u7684SQL\u8bed\u53e5\u5c06\u5bf9Boolean\u8fd4\u56de\u503c\u4e3atrue\u7684\u884c\u8fdb\u884c\u66f4\u65b0,\u82e5\u7701\u7565\u4e86WHERE\u5b50\u53e5,\u5219Boolean\u9ed8\u8ba4\u503c\u4e3atrue,\u4e5f\u5c31\u662f\u6240\u6709\u884c\u90fd\u4f1a\u88ab\u66f4\u65b0!<\/p>\n<p id=\"20251107203607-t8j0s07\">\u793a\u4f8b(\u5c06\u4e00\u4f4d\u7528\u6237\u7684\u59d3\u540d\u4eceA\u4fee\u6539\u5230B):<\/p>\n<pre class=\"wp-block-code\"><code>UPDATE \n    Person\nSET \n    Name='B'\nWHERE \n    Name='A';\n<\/code><\/pre>\n<h3 class=\"wp-block-heading\" id=\"DELETE-\u5220\u9664\u6570\u636e\">DELETE \u5220\u9664\u6570\u636e<\/h3>\n<pre class=\"wp-block-code\"><code>DELETE \nFROM \n    table_name\nWHERE \n    Boolean;\n<\/code><\/pre>\n<p id=\"20251107203813-lp6u7dp\">DELETE\u662f\u6309\u7167\u884c\u5220\u9664\u7684,\u6240\u4ee5\u4e0d\u9700\u8981\u6307\u5b9a\u5b57\u6bb5.<\/p>\n<p id=\"20251107203833-f6yasy0\">\u548cUPDATE\u4e00\u6837,\u5982\u679c\u7701\u7565\u4e86WHERE\u5b50\u53e5,Boolean\u7684\u9ed8\u8ba4\u503c\u662ftrue,\u8fd9\u4ee3\u8868\u5c06\u5220\u9664\u6240\u6709\u7684\u884c!<\/p>\n<h3 class=\"wp-block-heading\" id=\"TRUNCATE-TABLE-\u6e05\u9664\u8868\u6570\u636e\">TRUNCATE TABLE \u6e05\u9664\u8868\u6570\u636e<\/h3>\n<p id=\"20251107204129-pomoh5q\">\u8fd9\u6761\u6307\u4ee4\u4ec5\u4ec5\u4f1a\u5220\u9664\u8868\u4e2d\u7684\u6570\u636e,\u800c\u4e0d\u4f1a\u5220\u9664\u8868\u7684\u6846\u67b6\u7ed3\u6784<\/p>\n<pre class=\"wp-block-code\"><code>TRUNCATE TABLE \n    table_name;\n<\/code><\/pre>\n<h3 class=\"wp-block-heading\" id=\"DROP-TABLE-\u5220\u9664\u8868\">DROP TABLE \u5220\u9664\u8868<\/h3>\n<p id=\"20251107204151-bwqzjqm\">\u5220\u9664\u6574\u5f20\u8868,\u5305\u542b\u6846\u67b6\u7ed3\u6784<\/p>\n<pre class=\"wp-block-code\"><code>DROP TABLE \n    table_name;\n<\/code><\/pre>\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p>\u4eca\u5929\u7a81\u7136\u60f3\u5f00\u59cb\u66f4\u65b0BLOG,\u4e8e\u662f\u5c31\u6709\u4e86\u8fd9\u7bc7\u6587\u7ae0,\u662f\u4e00\u4e9b\u5f88\u57fa\u7840\u7684SQL\u8bed\u53e5,\u6572\u4e86\u4e00\u904d\u5c31\u5f53\u590d\u4e60\u4e86www.\u660e\u5929\u8981\u548c\u670b\u53cb\u4e00\u8d77\u8fd0\u8f6cCRH2A\u53bb\u626c\u5dde,\u5c1d\u5c1d\u626c\u5dde\u7092\u996d,\u7136\u540e\u8fd0\u8f6c\u516c\u4ea4\u53bb\u9547\u6c5f,\u6700\u540e\u4ece\u5927\u6e2f\u5357\u7ad9\u56de\u5357\u4eac,\u53c8\u662f\u4e00\u4e2a\u5145\u5b9e\u7684\u5468\u672b!!<\/p>\n<\/blockquote>","protected":false},"excerpt":{"rendered":"<p>SQL\u662f\u4e00\u95e8\u8f83\u4e3a\u901a\u7528\u7684\u7528\u6765\u64cd\u4f5c\u6570\u636e\u5e93\u7684\u8bed\u8a00,\u662f\u7528\u4e8e\u8bbf\u95ee\u548c\u5904\u7406\u6570\u636e\u5e93\u7684\u6807\u51c6\u7684\u8ba1\u7b97\u673a\u8bed\u8a00. \u6570\u636e\u5e93\u7ba1\u7406\u7cfb\u7edf\u53ef\u4ee5\u64cd\u4f5c [&hellip;]<\/p>","protected":false},"author":1,"featured_media":37,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11,3],"tags":[],"class_list":["post-33","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-11","category-coding"],"_links":{"self":[{"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/posts\/33","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/comments?post=33"}],"version-history":[{"count":2,"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/posts\/33\/revisions"}],"predecessor-version":[{"id":36,"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/posts\/33\/revisions\/36"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/media\/37"}],"wp:attachment":[{"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/media?parent=33"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/categories?post=33"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/tags?post=33"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}