{"id":96236,"date":"2024-10-20T07:44:19","date_gmt":"2024-10-19T23:44:19","guid":{"rendered":"https:\/\/server.hk\/cnblog\/96236\/"},"modified":"2024-10-20T07:44:20","modified_gmt":"2024-10-19T23:44:20","slug":"oracle%e4%b9%8bcharvarcharvarchar2%e7%9a%84%e6%af%94%e8%bc%83","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/96236\/","title":{"rendered":"Oracle\u4e4bChar,VarChar&amp;VarChar2\u7684\u6bd4\u8f03"},"content":{"rendered":"<h1 id=\"oracle%e4%b9%8bchar-varchar-varchar2%e7%9a%84%e6%af%94%e8%bc%83-ifWCJpLtHq\">Oracle\u4e4bChar, VarChar &amp; VarChar2\u7684\u6bd4\u8f03<\/h1>\n<p>\u5728Oracle\u8cc7\u6599\u5eab\u4e2d\uff0c\u5b57\u7b26\u6578\u64da\u985e\u578b\u7684\u9078\u64c7\u5c0d\u65bc\u6578\u64da\u7684\u5b58\u5132\u548c\u6027\u80fd\u6709\u8457\u91cd\u8981\u5f71\u97ff\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0eOracle\u4e2d\u7684\u4e09\u7a2e\u4e3b\u8981\u5b57\u7b26\u6578\u64da\u985e\u578b\uff1a<code>CHAR<\/code>\u3001<code>VARCHAR<\/code>\u548c<code>VARCHAR2<\/code>\uff0c\u4e26\u6bd4\u8f03\u5b83\u5011\u7684\u7279\u6027\u3001\u4f7f\u7528\u5834\u666f\u53ca\u6027\u80fd\u5dee\u7570\u3002<\/p>\n<h2 id=\"1-char%e6%95%b8%e6%93%9a%e9%a1%9e%e5%9e%8b-ifWCJpLtHq\">1. CHAR\u6578\u64da\u985e\u578b<\/h2>\n<p><code>CHAR<\/code>\u6578\u64da\u985e\u578b\u7528\u65bc\u5b58\u5132\u56fa\u5b9a\u9577\u5ea6\u7684\u5b57\u7b26\u6578\u64da\u3002\u7576\u5b9a\u7fa9\u4e00\u500b<code>CHAR<\/code>\u5b57\u6bb5\u6642\uff0c\u7121\u8ad6\u5be6\u969b\u5b58\u5132\u7684\u5b57\u7b26\u6578\u91cf\u662f\u591a\u5c11\uff0cOracle\u90fd\u6703\u70ba\u5176\u5206\u914d\u56fa\u5b9a\u7684\u7a7a\u9593\u3002\u4f8b\u5982\uff0c\u5982\u679c\u5b9a\u7fa9\u4e00\u500b<code>CHAR(10)<\/code>\u5b57\u6bb5\uff0c\u7121\u8ad6\u5be6\u969b\u5b58\u5132\u7684\u5b57\u7b26\u6578\u91cf\u662f5\u9084\u662f10\uff0cOracle\u90fd\u6703\u4f54\u752810\u500b\u5b57\u7b26\u7684\u7a7a\u9593\u3002<\/p>\n<ul>\n<li><strong>\u512a\u9ede\uff1a<\/strong>\u9069\u5408\u5b58\u5132\u9577\u5ea6\u56fa\u5b9a\u7684\u6578\u64da\uff0c\u5982\u570b\u5bb6\u4ee3\u78bc\u3001\u6027\u5225\u7b49\u3002<\/li>\n<li><strong>\u7f3a\u9ede\uff1a<\/strong>\u5982\u679c\u5b58\u5132\u7684\u6578\u64da\u9577\u5ea6\u5c0f\u65bc\u5b9a\u7fa9\u7684\u9577\u5ea6\uff0c\u6703\u6d6a\u8cbb\u7a7a\u9593\u3002<\/li>\n<\/ul>\n<h2 id=\"2-varchar%e6%95%b8%e6%93%9a%e9%a1%9e%e5%9e%8b-ifWCJpLtHq\">2. VARCHAR\u6578\u64da\u985e\u578b<\/h2>\n<p><code>VARCHAR<\/code>\u6578\u64da\u985e\u578b\u7528\u65bc\u5b58\u5132\u53ef\u8b8a\u9577\u5ea6\u7684\u5b57\u7b26\u6578\u64da\u3002\u8207<code>CHAR<\/code>\u4e0d\u540c\uff0c<code>VARCHAR<\/code>\u53ea\u4f54\u7528\u5be6\u969b\u5b58\u5132\u7684\u5b57\u7b26\u6578\u91cf\u52a0\u4e0a\u4e00\u500b\u984d\u5916\u7684\u5b57\u7bc0\u4f86\u5b58\u5132\u9577\u5ea6\u4fe1\u606f\u3002\u9019\u4f7f\u5f97<code>VARCHAR<\/code>\u5728\u5b58\u5132\u53ef\u8b8a\u9577\u5ea6\u7684\u6578\u64da\u6642\u66f4\u52a0\u9ad8\u6548\u3002<\/p>\n<ul>\n<li><strong>\u512a\u9ede\uff1a<\/strong>\u7bc0\u7701\u7a7a\u9593\uff0c\u9069\u5408\u5b58\u5132\u9577\u5ea6\u4e0d\u56fa\u5b9a\u7684\u6578\u64da\uff0c\u5982\u7528\u6236\u540d\u3001\u5730\u5740\u7b49\u3002<\/li>\n<li><strong>\u7f3a\u9ede\uff1a<\/strong>\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\uff0c\u6027\u80fd\u53ef\u80fd\u6703\u53d7\u5230\u5f71\u97ff\uff0c\u7279\u5225\u662f\u5728\u983b\u7e41\u66f4\u65b0\u7684\u60c5\u6cc1\u4e0b\u3002<\/li>\n<\/ul>\n<h2 id=\"3-varchar2%e6%95%b8%e6%93%9a%e9%a1%9e%e5%9e%8b-ifWCJpLtHq\">3. VARCHAR2\u6578\u64da\u985e\u578b<\/h2>\n<p><code>VARCHAR2<\/code>\u662fOracle\u63a8\u85a6\u4f7f\u7528\u7684\u53ef\u8b8a\u9577\u5ea6\u5b57\u7b26\u6578\u64da\u985e\u578b\u3002\u5b83\u7684\u884c\u70ba\u8207<code>VARCHAR<\/code>\u76f8\u4f3c\uff0c\u4f46\u6709\u4e00\u500b\u91cd\u8981\u7684\u5340\u5225\uff1a<code>VARCHAR2<\/code>\u5728\u5b58\u5132\u6642\u4e0d\u6703\u5c07\u7a7a\u5b57\u7b26\u4e32\u8996\u70baNULL\uff0c\u9019\u4f7f\u5f97\u5b83\u5728\u67d0\u4e9b\u61c9\u7528\u5834\u666f\u4e2d\u66f4\u52a0\u53ef\u9760\u3002<\/p>\n<ul>\n<li><strong>\u512a\u9ede\uff1a<\/strong>\u63d0\u4f9b\u66f4\u597d\u7684\u6027\u80fd\u548c\u7a7a\u9593\u5229\u7528\u7387\uff0c\u4e26\u4e14\u5728\u8655\u7406\u7a7a\u5b57\u7b26\u4e32\u6642\u884c\u70ba\u4e00\u81f4\u3002<\/li>\n<li><strong>\u7f3a\u9ede\uff1a<\/strong>\u5728\u67d0\u4e9b\u820a\u7248\u672c\u7684Oracle\u4e2d\uff0c<code>VARCHAR2<\/code>\u7684\u6700\u5927\u9577\u5ea6\u9650\u5236\u70ba4000\u5b57\u5143\u3002<\/li>\n<\/ul>\n<h2 id=\"4-%e6%80%a7%e8%83%bd%e6%af%94%e8%bc%83-ifWCJpLtHq\">4. \u6027\u80fd\u6bd4\u8f03<\/h2>\n<p>\u5728\u6027\u80fd\u65b9\u9762\uff0c<code>CHAR<\/code>\u3001<code>VARCHAR<\/code>\u548c<code>VARCHAR2<\/code>\u5404\u6709\u512a\u52a3\u3002<code>CHAR<\/code>\u5728\u8655\u7406\u56fa\u5b9a\u9577\u5ea6\u6578\u64da\u6642\u6027\u80fd\u8f03\u597d\uff0c\u4f46\u5728\u5b58\u5132\u53ef\u8b8a\u9577\u5ea6\u6578\u64da\u6642\u6703\u6d6a\u8cbb\u7a7a\u9593\u3002<code>VARCHAR<\/code>\u548c<code>VARCHAR2<\/code>\u5728\u5b58\u5132\u53ef\u8b8a\u9577\u5ea6\u6578\u64da\u6642\u66f4\u5177\u512a\u52e2\uff0c\u4f46\u5728\u983b\u7e41\u66f4\u65b0\u7684\u60c5\u6cc1\u4e0b\uff0c<code>VARCHAR<\/code>\u53ef\u80fd\u6703\u5c0e\u81f4\u6027\u80fd\u4e0b\u964d\u3002<\/p>\n<h2 id=\"5-%e4%bd%bf%e7%94%a8%e5%bb%ba%e8%ad%b0-ifWCJpLtHq\">5. \u4f7f\u7528\u5efa\u8b70<\/h2>\n<p>\u6839\u64da\u4e0d\u540c\u7684\u61c9\u7528\u5834\u666f\uff0c\u9078\u64c7\u5408\u9069\u7684\u6578\u64da\u985e\u578b\u81f3\u95dc\u91cd\u8981\uff1a<\/p>\n<ul>\n<li>\u5982\u679c\u6578\u64da\u9577\u5ea6\u56fa\u5b9a\uff0c\u5efa\u8b70\u4f7f\u7528<code>CHAR<\/code>\u3002<\/li>\n<li>\u5982\u679c\u6578\u64da\u9577\u5ea6\u4e0d\u56fa\u5b9a\uff0c\u4e14\u9700\u8981\u7bc0\u7701\u7a7a\u9593\uff0c\u5efa\u8b70\u4f7f\u7528<code>VARCHAR2<\/code>\u3002<\/li>\n<li>\u907f\u514d\u4f7f\u7528<code>VARCHAR<\/code>\uff0c\u56e0\u70ba\u5b83\u5728Oracle\u4e2d\u4e0d\u5982<code>VARCHAR2<\/code>\u53ef\u9760\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-ifWCJpLtHq\">\u7e3d\u7d50<\/h2>\n<p>\u5728Oracle\u8cc7\u6599\u5eab\u4e2d\uff0c<code>CHAR<\/code>\u3001<code>VARCHAR<\/code>\u548c<code>VARCHAR2<\/code>\u5404\u6709\u5176\u7279\u9ede\u548c\u9069\u7528\u5834\u666f\u3002\u9078\u64c7\u5408\u9069\u7684\u5b57\u7b26\u6578\u64da\u985e\u578b\u4e0d\u50c5\u80fd\u63d0\u9ad8\u6578\u64da\u5b58\u5132\u7684\u6548\u7387\uff0c\u9084\u80fd\u63d0\u5347\u7cfb\u7d71\u7684\u6574\u9ad4\u6027\u80fd\u3002\u5c0d\u65bc\u9700\u8981\u9ad8\u6548\u548c\u9748\u6d3b\u7684\u6578\u64da\u5b58\u5132\u89e3\u6c7a\u65b9\u6848\uff0c<code>VARCHAR2<\/code>\u662f\u6700\u63a8\u85a6\u7684\u9078\u64c7\u3002<\/p>\n<p>\u5982\u9700\u4e86\u89e3\u66f4\u591a\u6709\u95dc<code>VPS<\/code>\u3001<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u53ca\u5176\u4ed6\u76f8\u95dc\u670d\u52d9\u7684\u4fe1\u606f\uff0c\u8acb\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u6bd4\u8f03Oracle\u4e2d\u7684Char\u3001VarChar\u548cVarChar2\uff0c\u4e86\u89e3\u5b83\u5011\u7684\u5b58\u5132\u7279\u6027\u3001\u6027\u80fd\u5dee\u7570\u53ca\u9069\u7528\u5834\u666f\uff0c\u52a9\u60a8\u9078\u64c7\u6700\u4f73\u6578\u64da\u985e\u578b\u3002<\/p>\n","protected":false},"author":0,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-96236","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/96236","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=96236"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/96236\/revisions"}],"predecessor-version":[{"id":96237,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/96236\/revisions\/96237"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=96236"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=96236"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=96236"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}