{"id":573,"date":"2010-10-01T07:35:55","date_gmt":"2010-10-01T07:35:55","guid":{"rendered":"http:\/\/enjoyasp.net\/?p=573"},"modified":"2010-10-01T07:35:55","modified_gmt":"2010-10-01T07:35:55","slug":"null-%e5%8a%a0%e6%b3%95","status":"publish","type":"post","link":"https:\/\/enjoyasp.net\/index.php\/2010\/10\/01\/null-%e5%8a%a0%e6%b3%95\/","title":{"rendered":"NULL \u52a0\u6cd5"},"content":{"rendered":"<p> declare @OrderNo varchar(20)<br \/>\nset @OrderNo = &#8216;123&#8217; + null<\/p>\n<p>print @OrderNo<\/p>\n<p>\u7ed3\u679c\u4e3a\uff1aNULL \u4ec0\u4e48\u4e5f\u6ca1\u6709<br \/>\n\u5373\uff1a \u5b57\u7b26\u4e32 + NULL = NULL \uff08\u6b64\u70b9\u8981\u6ce8\u610f\uff01\uff09<br \/>\n\u6362\u7528 set @OrderNo = &#8216;123&#8217; + ISNULL\uff08@SDF, &#8221;\uff09<\/p>\n<p>NULL \u4e0e\u4efb\u4f55\u64cd\u4f5c\u90fd\u662fNULL \uff0c\u65e0\u8bba\u662f \u52a0\u6cd5\u8fd8\u662f\u903b\u8f91\u8fd0\u7b97<\/p>\n","protected":false},"excerpt":{"rendered":"<p>declare @OrderNo varchar(20) set @OrderNo = &#8216;123&#038; [&hellip;]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[36],"tags":[],"class_list":["post-573","post","type-post","status-publish","format-standard","hentry","category-sql-server"],"blocksy_meta":[],"_links":{"self":[{"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/posts\/573","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/comments?post=573"}],"version-history":[{"count":0,"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/posts\/573\/revisions"}],"wp:attachment":[{"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/media?parent=573"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/categories?post=573"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/tags?post=573"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}