涓€鍙ヨ瘽瀹炵幇MySQL搴撲腑鐨勬寜鏉′欢鍙樺寲鍒嗙粍

Posted 2020-12-07

鏍囩锛?a href='http://www.mamicode.com/so/1/from' title='from'>from   瀹屾垚   鎵ц   new   unbound   鏂逛究   select   鍑芥暟瀹炵幇   渚濇嵁   

杩欑鍒嗙粍鐨勪緷鎹槸姣旇緝涓婁竴琛屽瓧娈靛€硷紝鍙戠敓鏌愮鍙樺寲鏃讹紙濡傚彉澶ц秴杩?10锛変骇鐢熸柊缁勩€係QL 浠呮敮鎸佺瓑鍊煎垎缁勶紝瑕佹兂瀹炵幇杩欑鏈夊簭鏉′欢鍒嗙粍灏卞緱缁忚繃鍑犳鏁版嵁鍙樻崲锛屽彉鎹㈡垚绛夊€煎垎缁勩€備互鏀寔绐楀彛鍑芥暟鐨勬柊鐗?mysql 涓轰緥锛屽ぇ姒傜粡杩囪繖涔堜笁姝ワ細

1銆佸緱鍑哄彉鍖栨爣蹇楀瓧娈?flag銆傞€氳繃绐楀彛鍑芥暟 lag 寰楀埌涓婁竴琛岀殑瀛楁鍊硷紝婊¤冻鍙樺寲鏉′欢锛堝鏈 - 涓婁竴琛?>10锛塮lag 璁句负 1锛屽惁鍒欎负 0锛?/p>

2銆佺疮鍔?flag 瀛楁寰楀埌 acc 瀛楁銆備粠绗竴琛岀疮鍔犲埌褰撳墠琛岋紝杩樻槸寰楃敤绐楀彛鍑芥暟瀹炵幇锛歴um(flag)…BETWEEN ROWS UNBOUNDED AND CURRENT ROW锛?/p>

3銆佹寜 acc 瀛楁杩涜甯歌绛夊€煎垎缁勫嵆鍙€?/p>

鏃╂湡娌℃湁绐楀彛鍑芥暟鐨?MySQL锛岀悊璁轰笂涔熻兘瀹炵幇锛屾洿澶嶆潅锛屽氨涓嶇粏璇翠簡銆?/p>

 

杩欑被鏈夊簭鍒嗙粍濡傛灉鐢?SPL 璇█灏卞緢绠€鍗曪紝鐢?group 鎿嶄綔鐨?@i 閫夐」锛屼竴鍙ュ氨鎼炲畾浜嗭細

=connect(”mysqlDB”).query(“select * from t”).group@i(f>~[-1].f+10)

瀹屾垚鍒嗙粍鍔ㄤ綔鍚庯紝寰楀埌涓ゅ眰缁撴瀯鐨勫簭琛?B銆傚悗缁拡瀵圭浜屽眰鍒嗙粍瀛愰泦锛屽仛浠绘剰璁＄畻涔熼兘瀹规槗涓€鍙ユ悶瀹氾細

=B.max(~.len()) 寰楀埌鏈€澶х粍鐨勮鏁帮紱

=B.(~.new(f,avg(f2))).conj() 寰楀埌姣忕粍 f2 鐨勫钩鍧囧€硷紱

=B.(~.sort@z(f2).m(to(3))).conj() 鍙栧嚭姣忕粍 f2 鏈€澶х殑涓夎锛?/p>

闄や簡鏈夊簭鏉′欢鍒嗙粍锛岃繕鏈夋湁搴忕瓑鍊煎垎缁勶紝宓屽鍒嗙粍绛夊绉?SQL 闅惧疄鐜扮殑鍒嗙粍鏂瑰紡锛岃鎯呭弬鑰?a href="http://c.raqsoft.com.cn/article/1578647481899?from=HowtoLink" target="_blank">銆婂垎缁勫瓙闆嗐€?/a>銆?/p>

 

褰撴暟鎹笉鍦ㄦ暟鎹簱閲屾椂锛孲PL 鎵ц澶嶆潅璁＄畻浠嶇劧鏂逛究锛?br /> =file(“d:/t.csv”).import(;,",").group...

SPL鑳藉緢鏂逛究鍦板祵鍏ュ埌JAVA搴旂敤锛屽彲鍙傝€?a href="http://c.raqsoft.com.cn/article/1543657951867?from=HowtoLink" target="_blank">銆奐ava 濡備綍璋冪敤 SPL 鑴氭湰銆?/a>銆?/p>

鍏蜂綋浣跨敤鏂规硶鍙弬鑰?銆婂浣曚娇鐢ㄩ泦绠楀櫒銆?/a>銆?/p>