From user-return-27116-archive-asf-public=cust-asf.ponee.io@ignite.apache.org Fri Sep 13 19:23:48 2019 Return-Path: X-Original-To: archive-asf-public@cust-asf.ponee.io Delivered-To: archive-asf-public@cust-asf.ponee.io Received: from mail.apache.org (hermes.apache.org [207.244.88.153]) by mx-eu-01.ponee.io (Postfix) with SMTP id 3A665180652 for ; Fri, 13 Sep 2019 21:23:48 +0200 (CEST) Received: (qmail 3695 invoked by uid 500); 13 Sep 2019 19:23:47 -0000 Mailing-List: contact user-help@ignite.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: user@ignite.apache.org Delivered-To: mailing list user@ignite.apache.org Received: (qmail 3684 invoked by uid 99); 13 Sep 2019 19:23:47 -0000 Received: from pnap-us-west-generic-nat.apache.org (HELO spamd3-us-west.apache.org) (209.188.14.142) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 13 Sep 2019 19:23:47 +0000 Received: from localhost (localhost [127.0.0.1]) by spamd3-us-west.apache.org (ASF Mail Server at spamd3-us-west.apache.org) with ESMTP id 9DC05180D05 for ; Fri, 13 Sep 2019 19:23:46 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at spamd3-us-west.apache.org X-Spam-Flag: NO X-Spam-Score: 0.972 X-Spam-Level: X-Spam-Status: No, score=0.972 tagged_above=-999 required=6.31 tests=[RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_PASS=-0.001, SPF_SOFTFAIL=0.972, URIBL_BLOCKED=0.001] autolearn=disabled Received: from mx1-ec2-va.apache.org ([10.40.0.8]) by localhost (spamd3-us-west.apache.org [10.40.0.10]) (amavisd-new, port 10024) with ESMTP id QqUjpEtW6-1S for ; Fri, 13 Sep 2019 19:23:43 +0000 (UTC) Received-SPF: Softfail (mailfrom) identity=mailfrom; client-ip=162.255.23.37; helo=n6.nabble.com; envelope-from=spoutnik@skynet.be; receiver= Received: from n6.nabble.com (n6.nabble.com [162.255.23.37]) by mx1-ec2-va.apache.org (ASF Mail Server at mx1-ec2-va.apache.org) with ESMTP id 313E7BC50D for ; Fri, 13 Sep 2019 19:23:42 +0000 (UTC) Received: from n6.nabble.com (localhost [127.0.0.1]) by n6.nabble.com (Postfix) with ESMTP id 654371119AB47 for ; Fri, 13 Sep 2019 12:23:41 -0700 (MST) Date: Fri, 13 Sep 2019 12:23:41 -0700 (MST) From: spoutnik_be To: user@ignite.apache.org Message-ID: <1568402621412-0.post@n6.nabble.com> In-Reply-To: <1568309196181-0.post@n6.nabble.com> References: <1568309196181-0.post@n6.nabble.com> Subject: Re: Ignite query performance with lots of joins MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit @Daniel Magda: following you comment on Stackoverflow, continuing the discussion here. This is most probably related to the number of joins, we'll evolve to a less normalized model for querying from Ignite. Couple of questions still remain: - How many joins can Ignite/H2 handle without significant performance drop (read something about H2 CBO out if more than 7 joins)? - How to correctly interpret explain plan, especially with ANALYZE option and its scanCount? - Does order of query matters, Oracle CBO uses statistics to re-order joins while this is not visible in H2 explain plans. Any hints/info welcome ... Thanks, L. -- Sent from: http://apache-ignite-users.70518.x6.nabble.com/