{"id":1790,"date":"2015-04-22T17:11:30","date_gmt":"2015-04-22T09:11:30","guid":{"rendered":"http:\/\/www.821121.com\/?p=1790"},"modified":"2022-10-12T09:28:32","modified_gmt":"2022-10-12T01:28:32","slug":"%e5%ad%a6%e4%b9%a0%e7%ac%94%e8%ae%b0%e4%b9%8bsql%e5%88%86%e9%a1%b5","status":"publish","type":"post","link":"http:\/\/www.821121.com\/?p=1790","title":{"rendered":"\u5b66\u4e60\u7b14\u8bb0\u4e4bSQL\u5206\u9875"},"content":{"rendered":"<p>\u5b66\u4e60SQL\u8bed\u53e5\u4e2d\u6709\u4e2a\u7ecf\u5178\u7684\u9898\u76ee\uff0c\u6bd4\u5982\u67e5\u8be2\u85aa\u6c34\u7684\u524d5\u540d\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u6392\u5e8f\u4e4b\u540erownum&lt;=5\u6765\u67e5\u8be2\u3002<\/p>\n<pre><code class=\"language-shell\">select * from (select * from emp order by sal desc) hh where rownum&lt;=5;<\/code><\/pre>\n<p>\u6ce8:rownum\u662f\u9690\u85cf\u5217\uff0c\u6b64\u5916rowid\u662f64\u4f4d\u8fdb\u5236\u7684\u9690\u85cf\u5217\uff0c\u4e0d\u5b58\u5728\u4e8e\u4e34\u65f6\u8868\u4e2d\u3002<\/p>\n<p>\u5982\u679c\u60f3\u8981\u53d6\u4e2d\u95f45-10\u540d\u7684\u6570\u636e\u53c8\u8be5\u5982\u4f55\u5199SQL\u8bed\u53e5\u5462\uff1f\u7531\u4e8e\u4e71\u5e8f\u7684rownum\u65e0\u6cd5\u67e5\u8be2\uff0c\u6240\u4ee5\u53d6\u4e2d\u95f4\u8303\u56f4\u9700\u8981\u5904\u7406\uff0c\u5206\u9875\u68c0\u7d22\u3002\u8fd9\u91cc\u63d0\u4f9b3\u79cd\u65b9\u6cd5\uff1a<\/p>\n<h4>1.\u4e24\u4e2a\u76f8\u51cf<\/h4>\n<pre><code class=\"language-shell\">select t1.*,rownum oua from (select t.*,rownum ina from emp t order by sal desc) t1\nwhere rownum&lt;=10\nminus\nselect t2.*,rownum oua from (select tt.*,rownum ina from emp tt order by sal desc) t2\nwhere rownum&lt;=5;<\/code><\/pre>\n<h4>2.\u5728\u5916\u9762\u518d\u5d4c\u5957\uff0c\u5c31\u80fd\u4f7f\u7528rownum&gt;=\u4e86\uff0c\u6b64\u65f6\u662f\u6709\u5e8f\u7684\u3002<\/h4>\n<pre><code class=\"language-shell\">select t1.*,rownum r1 from (select t2.*,rownum r2 from (select e.*,rownum r3 from emp e order by sal desc)t2)t1 \nwhere r2&gt;=6 and r2&lt;=10;<\/code><\/pre>\n<h4>3.\u6cd53:\u7528offset \u548c fetch \u53d6<\/h4>\n<pre><code class=\"language-shell\">select t.*,rownum from emp t order by sal desc \noffset 0 row\nfetch next 5 row only;<\/code><\/pre>\n<p>\u6ce8\uff1a0\u662f\u8d77\u59cb\uff0cnext5\u662f\u53d6\u591a\u5c11\u6761\uff0c\u5373\u504f\u79fb\u91cf\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b66\u4e60SQL\u8bed\u53e5\u4e2d\u6709\u4e2a\u7ecf\u5178\u7684\u9898\u76ee\uff0c\u6bd4\u5982\u67e5\u8be2\u85aa\u6c34\u7684\u524d5<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-1790","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"http:\/\/www.821121.com\/index.php?rest_route=\/wp\/v2\/posts\/1790","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=1790"}],"version-history":[{"count":1,"href":"http:\/\/www.821121.com\/index.php?rest_route=\/wp\/v2\/posts\/1790\/revisions"}],"predecessor-version":[{"id":1791,"href":"http:\/\/www.821121.com\/index.php?rest_route=\/wp\/v2\/posts\/1790\/revisions\/1791"}],"wp:attachment":[{"href":"http:\/\/www.821121.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1790"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.821121.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1790"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.821121.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1790"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}