Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.84_2) (envelope-from ) id 1e8m4y-0002C6-UN for pgsql-performance@arkaria.postgresql.org; Sun, 29 Oct 2017 11:48:37 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.84_2) (envelope-from ) id 1e8m4x-0006Qs-U1 for pgsql-performance@arkaria.postgresql.org; Sun, 29 Oct 2017 11:48:35 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.84_2) (envelope-from ) id 1e8m3E-0003MX-Nc for pgsql-performance@postgresql.org; Sun, 29 Oct 2017 11:46:48 +0000 Received: from mail-ua0-x22c.google.com ([2607:f8b0:400c:c08::22c]) by magus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.84_2) (envelope-from ) id 1e8m3B-00016c-Ax for pgsql-performance@postgresql.org; Sun, 29 Oct 2017 11:46:48 +0000 Received: by mail-ua0-x22c.google.com with SMTP id s41so7671433uab.10 for ; Sun, 29 Oct 2017 04:46:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=2ndquadrant-com.20150623.gappssmtp.com; s=20150623; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=W+JayYEn8Tq2SrLcQn1bfr/krV1dgRg42aLOzJi5ipg=; b=heWqK1WYunQkz5ayvjDtyW30fwpntgSi9qrbvCErnSQUsauUcsyXMJoCwqGiOaXhfU o5A+jKWjhKu37ISIXxQS+Mb5eYXQYNG5arHa1mOp4tW/KD7kFfaMwDe8C+bM50aplrE5 VO5oIu2B+r2+/+84Hy3kFTWU2EYD5VKPPUvHPA85ga1UAs53t5DpY8Subw/rWLjuxDD5 Q9DNDMBHgykif5l8v2E1dxYLduZwNRrCaDdji6wvNaYKOy39qQ/AaODydUOt3s/Lqxjx HDBupPUhzmxwHMu427uUEj4tCZ321R89OhMvn32vNmPI7gusr3rKoHgq2E6I0HLQszar RNmg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=W+JayYEn8Tq2SrLcQn1bfr/krV1dgRg42aLOzJi5ipg=; b=JWYTjh1w2bWM9NNpAsnTtF8VuhESZTC2gzdbpn6ksKTKUt2HchDGE1kNJDgOkD47kf pz4PWEYLX1HF1XhXA3nWjTEBDqMYC08CxgA+XPiYdEL4eHFI1TKsdb0f9WvHPot2DVAm X1iM5eU1/byV+dKIZnmh1VayjbHUy0mx1sqQep6LjNrQlGNPwHEoQ0kdTHoajo3ZJne4 oouBVnw2qB65IuIi46CxP7jL+iiP/OYENTCfijR93k6DKq7vDJFdhHpY/0LXULGPM0fa X/FJciHILOYzxh/8jd2ve99B2kN0CR7Hlm4hlHkKFY51R3JqMFPYaTbKCpkO/blIhDDv FYFA== X-Gm-Message-State: AMCzsaWcoOUDublveWBAZFLgIDS4IbK++73Wq4BNILF5p4YGAXuHXuEK soBWp7ZF+1RoawEL3jTbKKanCg1Qkh4uUCJLYyRGKg== X-Google-Smtp-Source: ABhQp+Rg7vGzW2neIA2VvFecelb8xAdiSs9e7fWnjiI2hTCb5uBSBtQP8tt2wRP8jO69rqzrUZ9+m6ZTPikqfOpbY2Q= X-Received: by 10.159.63.15 with SMTP id h15mr5499548uaj.156.1509277602615; Sun, 29 Oct 2017 04:46:42 -0700 (PDT) MIME-Version: 1.0 Received: by 10.159.50.104 with HTTP; Sun, 29 Oct 2017 04:46:42 -0700 (PDT) In-Reply-To: <20171029112420.8920B5FB05@mx.zeyos.com> References: <20171029112420.8920B5FB05@mx.zeyos.com> From: David Rowley Date: Mon, 30 Oct 2017 00:46:42 +1300 Message-ID: Subject: Re: Cheaper subquery scan not considered unless offset 0 To: Benjamin Coutu Cc: postgres performance list , Tom Lane Content-Type: text/plain; charset="UTF-8" List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-performance Precedence: bulk Sender: pgsql-performance-owner@postgresql.org On 30 October 2017 at 00:24, Benjamin Coutu wrote: > -> Index Scan using "PK_items_ID" on items a (cost=0.42..1.05 rows=1 width=332) (actual time=0.003..0.003 rows=1 loops=15521 total=46.563) I've never seen EXPLAIN output like that before. Is this some modified version of PostgreSQL? -- David Rowley http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance