{"id":1088,"date":"2015-04-17T15:34:09","date_gmt":"2015-04-17T07:34:09","guid":{"rendered":"http:\/\/www.821121.com\/?p=1088"},"modified":"2020-12-15T16:04:27","modified_gmt":"2020-12-15T08:04:27","slug":"oracle-sql%e8%af%ad%e5%8f%a5-%e4%b9%8b-nvl%e5%87%bd%e6%95%b0","status":"publish","type":"post","link":"http:\/\/www.821121.com\/?p=1088","title":{"rendered":"Oracle SQL\u8bed\u53e5 \u4e4b NVL\u51fd\u6570"},"content":{"rendered":"<h1>\u5b9a\u4e49<\/h1>\n<p>nvl\u7cfb\u5217\u51fd\u6570\u4e3b\u8981\u662f\u4e3a\u4e86\u5b9e\u73b0\u7a7a\u503c\u7684\u8f6c\u6362\uff0c\u4e3b\u8981\u7528\u4e8e\u5bf9\u6570\u636e\u5217\u4e0a\u7684\u7a7a\u503c\u8fdb\u884c\u5904\u7406\u3002<\/p>\n<h1>\u8bed\u6cd5<\/h1>\n<p>nvl\u51fd\u6570\uff1a\u57fa\u672c\u8bed\u6cd5\u4e3anvl(a,b)\uff0c\u610f\u601d\u662f\u4e24\u4e2a\u5b57\u6bb5\u4e2d\u7684\u6570\u636e\u5982\u679c\u6709\u4e3anull\u7684\uff0c\u5c31\u8fd4\u56deb\uff0c\u4e0d\u4e3anull\u5c31\u8fd4\u56dea\u3002<\/p>\n<p>nvl2\u51fd\u6570\u662fnvl\u51fd\u6570\u7684\u62d3\u5c55\uff0c\u57fa\u672c\u8bed\u6cd5\u4e3anvl2(a,b,c)\uff0c\u610f\u601d\u662f\u5982\u679ca\u4e3anull\uff0c\u5c31\u8fd4\u56dec\uff0c\u4e0d\u4e3anull\u5c31\u8fd4\u56deb\u3002<\/p>\n<h1>\u8fd4\u56de\u503c\u7c7b\u578b<\/h1>\n<p>\u53ef\u4ee5\u4e3a\u5b57\u7b26\u578b\u3001\u65e5\u671f\u578b\u3001\u65e5\u671f\u65f6\u95f4\u578b\u3001\u6570\u503c\u578b\u3001\u8d27\u5e01\u578b\u3001\u903b\u8f91\u578b\u6216null\u503c\u3002<\/p>\n<h1>\u4e3e\u4f8b<\/h1>\n<h2>\u672a\u52a0\u51fd\u6570<\/h2>\n<pre><code class=\"language-sql\">select a.\u4e61\u9547, a.\u8857\u9053 from zyjjzb a<\/code><\/pre>\n<p><img decoding=\"async\" src=\"\/wp-content\/uploads\/2020\/12\/image-1608017477191.png\" alt=\"file\" \/><\/p>\n<h2>\u4f7f\u7528nvl\u51fd\u6570<\/h2>\n<pre><code class=\"language-sql\">select nvl(a.\u4e61\u9547, a.\u8857\u9053)&quot;\u4e61\u9547\u8857\u9053&quot; from zyjjzb a<\/code><\/pre>\n<p><img decoding=\"async\" src=\"\/wp-content\/uploads\/2020\/12\/image-1608017555530.png\" alt=\"file\" \/><\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b9a\u4e49 nvl\u7cfb\u5217\u51fd\u6570\u4e3b\u8981\u662f\u4e3a\u4e86\u5b9e\u73b0\u7a7a\u503c\u7684\u8f6c\u6362\uff0c\u4e3b\u8981<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[48],"tags":[],"class_list":["post-1088","post","type-post","status-publish","format-standard","hentry","category-sql"],"_links":{"self":[{"href":"http:\/\/www.821121.com\/index.php?rest_route=\/wp\/v2\/posts\/1088","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.821121.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.821121.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.821121.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.821121.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1088"}],"version-history":[{"count":2,"href":"http:\/\/www.821121.com\/index.php?rest_route=\/wp\/v2\/posts\/1088\/revisions"}],"predecessor-version":[{"id":1099,"href":"http:\/\/www.821121.com\/index.php?rest_route=\/wp\/v2\/posts\/1088\/revisions\/1099"}],"wp:attachment":[{"href":"http:\/\/www.821121.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1088"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.821121.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1088"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.821121.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1088"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}