{"id":187660,"date":"2024-11-11T16:07:24","date_gmt":"2024-11-11T08:07:24","guid":{"rendered":"https:\/\/server.hk\/cnblog\/187660\/"},"modified":"2024-11-11T16:07:25","modified_gmt":"2024-11-11T08:07:25","slug":"%e6%95%b8%e6%93%9a%e5%ba%ab%e6%80%8e%e9%ba%bc%e4%bf%ae%e6%94%b9%e5%ad%97%e6%ae%b5%e5%85%81%e8%a8%b1%e7%82%ba%e7%a9%ba%ef%bc%9f-%e6%95%b8%e6%93%9a%e5%ba%ab%e5%a6%82%e4%bd%95%e4%bf%ae%e6%94%b9%e5%85%81","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/187660\/","title":{"rendered":"\u6578\u64da\u5eab\u600e\u9ebc\u4fee\u6539\u5b57\u6bb5\u5141\u8a31\u70ba\u7a7a\uff1f (\u6578\u64da\u5eab\u5982\u4f55\u4fee\u6539\u5141\u8a31\u70ba\u7a7a)"},"content":{"rendered":"<h1 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\u8868\u540d MODIFY COLUMN \u5b57\u6bb5\u540d \u6578\u64da\u985e\u578b [NULL | NOT NULL];<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u5047\u8a2d\u6709\u4e00\u500b\u540d\u70ba\u201cusers\u201d\u7684\u8868\uff0c\u4e26\u4e14\u60f3\u8981\u5c07\u201cemail\u201d\u5b57\u6bb5\u7684\u5141\u8a31\u70ba\u7a7a\u5c6c\u6027\u8a2d\u7f6e\u70ba\u5141\u8a31\u70ba\u7a7a\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a<\/p>\n<pre><code>ALTER TABLE users MODIFY COLUMN email VARCHAR(255) NULL;<\/code><\/pre>\n<p>\u5982\u679c\u60f3\u8981\u5c07\u201cemail\u201d\u5b57\u6bb5\u8a2d\u7f6e\u70ba\u4e0d\u5141\u8a31\u70ba\u7a7a\uff0c\u53ef\u4ee5\u4f7f\u7528\uff1a<\/p>\n<pre><code>ALTER TABLE users MODIFY COLUMN email VARCHAR(255) NOT NULL;<\/code><\/pre>\n<h2 id=\"%e5%9c%a8postgresql%e4%b8%ad%e4%bf%ae%e6%94%b9%e5%ad%97%e6%ae%b5%e5%85%81%e8%a8%b1%e7%82%ba%e7%a9%ba-yhxlaONkCk\">\u5728PostgreSQL\u4e2d\u4fee\u6539\u5b57\u6bb5\u5141\u8a31\u70ba\u7a7a<\/h2>\n<p>\u5728PostgreSQL\u4e2d\uff0c\u4fee\u6539\u5b57\u6bb5\u7684\u5141\u8a31\u70ba\u7a7a\u5c6c\u6027\u540c\u6a23\u4f7f\u7528ALTER TABLE\u8a9e\u53e5\u3002\u8a9e\u6cd5\u8207MySQL\u985e\u4f3c\uff1a<\/p>\n<pre><code>ALTER TABLE \u8868\u540d ALTER COLUMN \u5b57\u6bb5\u540d SET [NOT] NULL;<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u5c07\u201cemail\u201d\u5b57\u6bb5\u8a2d\u7f6e\u70ba\u5141\u8a31\u70ba\u7a7a\u7684\u547d\u4ee4\u5982\u4e0b\uff1a<\/p>\n<pre><code>ALTER TABLE users ALTER COLUMN email DROP NOT NULL;<\/code><\/pre>\n<p>\u800c\u5c07\u5176\u8a2d\u7f6e\u70ba\u4e0d\u5141\u8a31\u70ba\u7a7a\u7684\u547d\u4ee4\u5247\u70ba\uff1a<\/p>\n<pre><code>ALTER TABLE users ALTER COLUMN email SET NOT NULL;<\/code><\/pre>\n<h2 id=\"%e5%9c%a8sql-server%e4%b8%ad%e4%bf%ae%e6%94%b9%e5%ad%97%e6%ae%b5%e5%85%81%e8%a8%b1%e7%82%ba%e7%a9%ba-yhxlaONkCk\">\u5728SQL Server\u4e2d\u4fee\u6539\u5b57\u6bb5\u5141\u8a31\u70ba\u7a7a<\/h2>\n<p>\u5728SQL Server\u4e2d\uff0c\u4fee\u6539\u5b57\u6bb5\u7684\u5141\u8a31\u70ba\u7a7a\u5c6c\u6027\u4e5f\u53ef\u4ee5\u901a\u904eALTER TABLE\u8a9e\u53e5\u4f86\u5be6\u73fe\u3002\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>ALTER TABLE \u8868\u540d ALTER COLUMN \u5b57\u6bb5\u540d \u6578\u64da\u985e\u578b [NULL | NOT NULL];<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u5c07\u201cemail\u201d\u5b57\u6bb5\u8a2d\u7f6e\u70ba\u5141\u8a31\u70ba\u7a7a\u7684\u547d\u4ee4\u5982\u4e0b\uff1a<\/p>\n<pre><code>ALTER TABLE users ALTER COLUMN email VARCHAR(255) NULL;<\/code><\/pre>\n<p>\u800c\u5c07\u5176\u8a2d\u7f6e\u70ba\u4e0d\u5141\u8a31\u70ba\u7a7a\u7684\u547d\u4ee4\u5247\u70ba\uff1a<\/p>\n<pre><code>ALTER TABLE users ALTER COLUMN email VARCHAR(255) NOT NULL;<\/code><\/pre>\n<h2 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id=\"%e7%b8%bd%e7%b5%90-yhxlaONkCk\">\u7e3d\u7d50<\/h2>\n<p>\u4fee\u6539\u6578\u64da\u5eab\u5b57\u6bb5\u7684\u5141\u8a31\u70ba\u7a7a\u5c6c\u6027\u662f\u4e00\u500b\u5e38\u898b\u7684\u9700\u6c42\uff0c\u7121\u8ad6\u662f\u5728MySQL\u3001PostgreSQL\u9084\u662fSQL Server\u4e2d\uff0c\u9019\u4e00\u904e\u7a0b\u90fd\u76f8\u5c0d\u7c21\u55ae\u3002\u901a\u904e\u4f7f\u7528ALTER TABLE\u8a9e\u53e5\uff0c\u60a8\u53ef\u4ee5\u9748\u6d3b\u5730\u8abf\u6574\u6578\u64da\u5eab\u7d50\u69cb\uff0c\u4ee5\u6eff\u8db3\u4e0d\u65b7\u8b8a\u5316\u7684\u696d\u52d9\u9700\u6c42\u3002\u5c0d\u65bc\u9700\u8981\u9ad8\u6548\u7ba1\u7406\u6578\u64da\u5eab\u7684\u4f01\u696d\u4f86\u8aaa\uff0c\u9078\u64c7\u5408\u9069\u7684\u6578\u64da\u5eab\u89e3\u6c7a\u65b9\u6848\u81f3\u95dc\u91cd\u8981\u3002\u82e5\u60a8\u5c0d\u65bcVPS\u6216\u5176\u4ed6\u96f2\u670d\u52d9\u6709\u8208\u8da3\uff0c\u6b61\u8fce\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u4e86\u89e3\u66f4\u591a\u8cc7\u8a0a\uff0c\u63a2\u7d22\u6211\u5011\u7684<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u89e3\u6c7a\u65b9\u6848\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b78\u7fd2\u5982\u4f55\u5728\u6578\u64da\u5eab\u4e2d\u4fee\u6539\u5b57\u6bb5\u8a2d\u7f6e\u4ee5\u5141\u8a31\u7a7a\u503c\uff0c\u7c21\u55ae\u6b65\u9a5f\u52a9\u4f60\u8f15\u9b06\u5b8c\u6210\u6578\u64da\u5eab\u7ba1\u7406\u4efb\u52d9\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-187660","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/187660","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=187660"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/187660\/revisions"}],"predecessor-version":[{"id":187661,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/187660\/revisions\/187661"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=187660"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=187660"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=187660"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}