{"id":15811,"date":"2023-12-04T23:00:24","date_gmt":"2023-12-04T15:00:24","guid":{"rendered":"https:\/\/wx.kaifamiao.info\/?p=15811"},"modified":"2023-12-04T23:12:08","modified_gmt":"2023-12-04T15:12:08","slug":"oracle-zhong-jing-chang-shi-yong-dao-de-han-shu","status":"publish","type":"post","link":"http:\/\/wx.kaifamiao.info\/index.php\/2023\/12\/04\/oracle-zhong-jing-chang-shi-yong-dao-de-han-shu\/","title":{"rendered":"Oracle \u4e2d\u7ecf\u5e38\u4f7f\u7528\u5230\u7684\u51fd\u6570\uff1f"},"content":{"rendered":"<p>Oracle\u6570\u636e\u5e93\u63d0\u4f9b\u4e86\u4e30\u5bcc\u7684\u5185\u7f6e\u51fd\u6570\uff0c\u7528\u4e8e\u6267\u884c\u5404\u79cd\u64cd\u4f5c\uff0c\u5305\u62ec\u5b57\u7b26\u4e32\u5904\u7406\u3001\u6570\u5b66\u8fd0\u7b97\u3001\u65e5\u671f\u5904\u7406\u3001\u805a\u5408\u64cd\u4f5c\u7b49\u3002\u4ee5\u4e0b\u662f\u4e00\u4e9b\u7ecf\u5e38\u5728Oracle\u4e2d\u4f7f\u7528\u7684\u51fd\u6570\uff1a<\/p>\n<ol>\n<li><strong>\u5b57\u7b26\u4e32\u51fd\u6570\uff1a<\/strong>\n<ul>\n<li><code>CONCAT<\/code> \u6216 <code>||<\/code>: \u5b57\u7b26\u4e32\u8fde\u63a5\u3002<\/li>\n<li><code>SUBSTR<\/code>\uff1a\u63d0\u53d6\u5b50\u5b57\u7b26\u4e32\u3002<\/li>\n<li><code>INSTR<\/code>\uff1a\u67e5\u627e\u5b57\u7b26\u4e32\u5728\u53e6\u4e00\u4e2a\u5b57\u7b26\u4e32\u4e2d\u7684\u4f4d\u7f6e\u3002<\/li>\n<li><code>LENGTH<\/code>\uff1a\u8fd4\u56de\u5b57\u7b26\u4e32\u957f\u5ea6\u3002<\/li>\n<li><code>UPPER<\/code> \u548c <code>LOWER<\/code>\uff1a\u5c06\u5b57\u7b26\u4e32\u8f6c\u6362\u4e3a\u5927\u5199\u6216\u5c0f\u5199\u3002<\/li>\n<\/ul>\n<\/li>\n<li><strong>\u6570\u5b66\u51fd\u6570\uff1a<\/strong>\n<ul>\n<li><code>ROUND<\/code>\uff1a\u56db\u820d\u4e94\u5165\u3002<\/li>\n<li><code>TRUNC<\/code>\uff1a\u622a\u65ad\u5c0f\u6570\u90e8\u5206\u3002<\/li>\n<li><code>MOD<\/code>\uff1a\u8fd4\u56de\u4f59\u6570\u3002<\/li>\n<li><code>ABS<\/code>\uff1a\u8fd4\u56de\u7edd\u5bf9\u503c\u3002<\/li>\n<\/ul>\n<\/li>\n<li><strong>\u65e5\u671f\u51fd\u6570\uff1a<\/strong>\n<ul>\n<li><code>SYSDATE<\/code>\uff1a\u8fd4\u56de\u5f53\u524d\u65e5\u671f\u548c\u65f6\u95f4\u3002<\/li>\n<li><code>TO_DATE<\/code>\uff1a\u5c06\u5b57\u7b26\u4e32\u8f6c\u6362\u4e3a\u65e5\u671f\u3002<\/li>\n<li><code>TO_CHAR<\/code>\uff1a\u5c06\u65e5\u671f\u8f6c\u6362\u4e3a\u5b57\u7b26\u4e32\u3002<\/li>\n<li><code>MONTHS_BETWEEN<\/code>\uff1a\u8ba1\u7b97\u4e24\u4e2a\u65e5\u671f\u4e4b\u95f4\u7684\u6708\u6570\u3002<\/li>\n<li><code>ADD_MONTHS<\/code>\uff1a\u5728\u65e5\u671f\u4e0a\u6dfb\u52a0\u6708\u4efd\u3002<\/li>\n<li><code>LAST_DAY<\/code>\uff1a\u8fd4\u56de\u6708\u7684\u6700\u540e\u4e00\u5929\u3002<\/li>\n<\/ul>\n<\/li>\n<li><strong>\u805a\u5408\u51fd\u6570\uff1a<\/strong>\n<ul>\n<li><code>SUM<\/code>\uff1a\u8ba1\u7b97\u603b\u548c\u3002<\/li>\n<li><code>AVG<\/code>\uff1a\u8ba1\u7b97\u5e73\u5747\u503c\u3002<\/li>\n<li><code>MIN<\/code> \u548c <code>MAX<\/code>\uff1a\u627e\u5230\u6700\u5c0f\u503c\u548c\u6700\u5927\u503c\u3002<\/li>\n<li><code>COUNT<\/code>\uff1a\u8ba1\u7b97\u884c\u6570\u3002<\/li>\n<\/ul>\n<\/li>\n<li><strong>\u6761\u4ef6\u51fd\u6570\uff1a<\/strong>\n<ul>\n<li><code>CASE<\/code>\uff1a\u6267\u884c\u6761\u4ef6\u5224\u65ad\u3002<\/li>\n<li><code>NVL<\/code>\uff1a\u5982\u679c\u8868\u8fbe\u5f0f\u4e3a null\uff0c\u5219\u8fd4\u56de\u6307\u5b9a\u7684\u66ff\u4ee3\u503c\u3002<\/li>\n<li><code>DECODE<\/code>\uff1a\u7c7b\u4f3c\u4e8e <code>CASE<\/code>\uff0c\u7528\u4e8e\u6761\u4ef6\u5224\u65ad\u3002<\/li>\n<\/ul>\n<\/li>\n<li><strong>\u7c7b\u578b\u8f6c\u6362\u51fd\u6570\uff1a<\/strong>\n<ul>\n<li><code>TO_NUMBER<\/code>\uff1a\u5c06\u5b57\u7b26\u4e32\u8f6c\u6362\u4e3a\u6570\u5b57\u3002<\/li>\n<li><code>TO_DATE<\/code>\uff1a\u5c06\u5b57\u7b26\u4e32\u8f6c\u6362\u4e3a\u65e5\u671f\u3002<\/li>\n<\/ul>\n<\/li>\n<li><strong>\u5206\u6790\u51fd\u6570\uff1a<\/strong>\n<ul>\n<li><code>RANK<\/code>\u3001<code>DENSE_RANK<\/code> \u548c <code>ROW_NUMBER<\/code>\uff1a\u7528\u4e8e\u6267\u884c\u6392\u540d\u64cd\u4f5c\u3002<\/li>\n<li><code>LAG<\/code> \u548c <code>LEAD<\/code>\uff1a\u83b7\u53d6\u524d\u4e00\u884c\u6216\u540e\u4e00\u884c\u7684\u503c\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n<p>\u8fd9\u4e9b\u51fd\u6570\u53ef\u4ee5\u5728 <code>SELECT<\/code> \u8bed\u53e5\u3001<code>WHERE<\/code> \u5b50\u53e5\u3001<code>ORDER BY<\/code> \u5b50\u53e5\u7b49\u5730\u65b9\u4f7f\u7528\uff0c\u7528\u4e8e\u5bf9\u6570\u636e\u8fdb\u884c\u5904\u7406\u548c\u5206\u6790\u3002\u5177\u4f53\u4f7f\u7528\u54ea\u4e9b\u51fd\u6570\u53d6\u51b3\u4e8e\u5177\u4f53\u7684\u9700\u6c42\u548c\u6570\u636e\u5904\u7406\u573a\u666f\u3002\u5728\u7f16\u5199 SQL \u67e5\u8be2\u65f6\uff0c\u719f\u6089\u8fd9\u4e9b\u51fd\u6570\u80fd\u591f\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\u548c\u7075\u6d3b\u6027\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Oracle\u6570\u636e\u5e93\u63d0\u4f9b\u4e86\u4e30\u5bcc\u7684\u5185\u7f6e\u51fd\u6570\uff0c\u7528\u4e8e\u6267\u884c\u5404\u79cd\u64cd\u4f5c\uff0c\u5305\u62ec\u5b57\u7b26\u4e32\u5904\u7406\u3001\u6570\u5b66\u8fd0\u7b97\u3001\u65e5\u671f\u5904\u7406\u3001\u805a\u5408\u64cd\u4f5c\u7b49\u3002\u4ee5\u4e0b [&hellip;]<\/p>\n","protected":false},"author":11,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[120],"tags":[],"class_list":["post-15811","post","type-post","status-publish","format-standard","hentry","category-oracel"],"_links":{"self":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/15811","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/users\/11"}],"replies":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/comments?post=15811"}],"version-history":[{"count":1,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/15811\/revisions"}],"predecessor-version":[{"id":15812,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/15811\/revisions\/15812"}],"wp:attachment":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/media?parent=15811"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/categories?post=15811"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/tags?post=15811"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}