From b20195c13e42a2444699683d501fd93b84294689 Mon Sep 17 00:00:00 2001
From: Shigeru Hanada ãã³ãã¯ã¯ã¨ãªã®åã®ãããã¯ã³ã¡ã³ãå
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ã«ãªãã¸ã§ã¯ãåã¾ãã¯å¥å(ã¨ã¤ãªã¢ã¹)ã§æå®ãã¦ãã ããã 以ä¸ã®ä¾ã§ã¯ãHashJoinã¨SeqScanãã³ãã«ãããpgbench_accountsãã¼ãã«ã«å¯¾ããSeq Scanã®çµæãHash Joinããå®è¡è¨ç»ãé¸æããã¦ãã¾ãã ãã³ã対象ã®ãªãã¸ã§ã¯ãåã«å°æåã¨ã¢ã³ãã¼ã¹ã³ã¢(_)以å¤ã®æå(大æåãæ°åã空ç½ã¹ãã¼ã¹ãªã©)ãå«ãå ´åã¯ãããã«ã¯ã©ã¼ã(")ã§å²ãã§ãã ããã ã¾ããã¯ã¨ãªä¸ã«åä¸å称ã®ãã¼ãã«ãè¤æ°ååºç¾ããå ´å(ã¹ãã¼ãéããåä¸ãã¼ãã«ã®è¤æ°å使ç¨ãªã©)ã¯ããã¼ãã«ã«å¥åãã¤ãã¦ããããã®ãã¼ãã«ãåºå¥ãã¦ãã ããã以ä¸ã®ä¾ã®1ã¤ç®ã®SQLæã§ã¯ãMergeJoin(t1 t1)ããã³ãã«æå®ããã¨ãããã³ã対象ã®ãªãã¸ã§ã¯ããç¹å®ã§ããã«ã¨ã©ã¼ã«ãªã£ã¦ãã¾ãã2ã¤ç®ã®SQLæã§ã¯ãåãã¼ãã«ã«ptãstã¨ããå¥åãã¤ãã¦ãããããå®è¡è¨ç»ä½ææã«ãã³ãã§æå®ããéãã«Merge Joinãé¸æãã¦ãã¾ãã
+ ãã³ã対象ã®ãªãã¸ã§ã¯ãåã«å°æåã¨ã¢ã³ãã¼ã¹ã³ã¢(_)以å¤ã®æå(大æåãæ°åã空ç½ã¹ãã¼ã¹ãªã©)ãå«ãå ´åã¯ãããã«ã¯ã©ã¼ã(")ã§å²ãã§ãã ããããã³ãã®è¨è¿°æ¹æ³
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@@ -174,8 +174,11 @@ postgres-# ORDER BY a.aid;
postgres=#
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postgres=# /* MergeJoin(t1 t1)*/
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2.11.0