{"id":47743,"date":"2023-12-11T15:12:53","date_gmt":"2023-12-11T07:12:53","guid":{"rendered":"https:\/\/wx.kaifamiao.info\/?p=47743"},"modified":"2023-12-11T15:12:53","modified_gmt":"2023-12-11T07:12:53","slug":"%e6%98%af%e5%90%a6%e5%86%99%e8%bf%87udf%ef%bc%8c%e9%97%aeudaf%ef%bc%8cudtf%e5%8c%ba%e5%88%ab%e5%92%8c%e4%b8%80%e4%ba%9b%e7%bb%86%e8%8a%82%ef%bc%9f-4","status":"publish","type":"post","link":"http:\/\/wx.kaifamiao.info\/index.php\/2023\/12\/11\/%e6%98%af%e5%90%a6%e5%86%99%e8%bf%87udf%ef%bc%8c%e9%97%aeudaf%ef%bc%8cudtf%e5%8c%ba%e5%88%ab%e5%92%8c%e4%b8%80%e4%ba%9b%e7%bb%86%e8%8a%82%ef%bc%9f-4\/","title":{"rendered":"\u662f\u5426\u5199\u8fc7udf\uff0c\u95eeudaf\uff0cudtf\u533a\u522b\u548c\u4e00\u4e9b\u7ec6\u8282\uff1f"},"content":{"rendered":"<p>&#8220;`&#8221;                    \u53c2\u8003\u56de\u7b54\uff1a<\/p>\n<p>udf:user defined function<\/p>\n<p>\u7279\u70b9\uff1ainput:output=1:1<\/p>\n<p>\u5b9e\u4f8b\u51fd\u6570:md5,split,ltrim<\/p>\n<p>\u5e94\u7528\u573a\u666f\uff1a1:1\u7684\u60c5\u51b5\uff0c\u6bd4\u5982md5&#8230;<\/p>\n<p>\u5b9e\u73b0\u65b9\u6cd5\uff1a\u7b80\u5355udf\u5b9e\u73b0<\/p>\n<p>extends UDF<\/p>\n<p>\u65b9\u6cd5\u540d evaluate<\/p>\n<p>udaf:user defined aggregation function<\/p>\n<p>\u7279\u70b9: input:output=n:1<\/p>\n<p>\u793a\u4f8b\u51fd\u6570\uff1asum,count,max,min&#8230;&#8230;<\/p>\n<p>\u5b9e\u73b0\u65b9\u6cd5\uff1aextends UDAF,\u5185\u90e8\u9759\u6001\u7c7b\u5b9e\u73b0\u63a5\u53e3UDAFEvaluator<\/p>\n<p>\u4e94\u5927\u65b9\u6cd5\uff1ainit:\u521d\u59cb\u5316map\u6216\u662freduce\u9700\u7528\u5230\u7684\u53d8\u91cf<\/p>\n<p>iterate:\u8fed\u4ee3\u5904\u7406\u6bcf\u6761\u6570\u636e\uff0ctrue<\/p>\n<p>terminatePartial:\u76f8\u5f53\u4e8emr\u7684combiner<\/p>\n<p>merge:\u5176\u8f93\u5165\u4e00\u5b9a\u662fterminatePartial\u7684\u8f93\u51fa<\/p>\n<p>terminate:\u5904\u7406\u7684\u662fmerge\u7684\u7ed3\u679c<\/p>\n<p>udtf:user defined table function<\/p>\n<p>\u7279\u70b9:input:output=1:n<\/p>\n<p>\u793a\u4f8b\u51fd\u6570\uff1aexplode<\/p>\n<p>\u5b9e\u73b0\u65b9\u6cd5\uff1audf+explode<\/p>\n<p>&lt;pre&gt;&lt;code&gt;            &quot;&#8220;`<br \/>\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>&#8220;`&#8221; \u53c2\u8003\u56de\u7b54\uff1a udf:user defined function \u7279\u70b9\uff1ainpu [&hellip;]<\/p>\n","protected":false},"author":7,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-47743","post","type-post","status-publish","format-standard","hentry","category-c"],"_links":{"self":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/47743","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\/7"}],"replies":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/comments?post=47743"}],"version-history":[{"count":1,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/47743\/revisions"}],"predecessor-version":[{"id":47744,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/47743\/revisions\/47744"}],"wp:attachment":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/media?parent=47743"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/categories?post=47743"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/tags?post=47743"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}