Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.84_2) (envelope-from ) id 1ai1wm-0005F6-Il for pgsql-general@arkaria.postgresql.org; Mon, 21 Mar 2016 15:40:48 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.84_2) (envelope-from ) id 1ai1wl-0003dZ-Tl for pgsql-general@arkaria.postgresql.org; Mon, 21 Mar 2016 15:40:47 +0000 Received: from makus.postgresql.org ([2001:4800:1501:1::229]) by malur.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.84_2) (envelope-from ) id 1ai1wk-0003b0-T7 for pgsql-general@postgresql.org; Mon, 21 Mar 2016 15:40:47 +0000 Received: from out1-smtp.messagingengine.com ([66.111.4.25]) by makus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.84_2) (envelope-from ) id 1ai1wi-0008Hw-3m for pgsql-general@postgresql.org; Mon, 21 Mar 2016 15:40:45 +0000 Received: from compute2.internal (compute2.nyi.internal [10.202.2.42]) by mailout.nyi.internal (Postfix) with ESMTP id 34C8620C31 for ; Mon, 21 Mar 2016 11:40:43 -0400 (EDT) Received: from frontend1 ([10.202.2.160]) by compute2.internal (MEProxy); Mon, 21 Mar 2016 11:40:43 -0400 DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d=aklaver.com; h=cc :content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-sasl-enc :x-sasl-enc; s=mesmtp; bh=u+8NDCtp2jaJp4IvtkuQRUJEMAc=; b=D0Tcsn JsSY9wfJ82EFNGDQ+TTFLj6gyl4S2o82YX6kjulvL76wC9b9gl1cJ0BlIESatn95 0WMAN22tYWXyeZ3NwMRf/UmDYLjrFr9q2y0G3kE2wbJ9rHnzHkUY86iffFhgAlnb ZJj2r9h7DD/mFEAJ2XFq9zY6faeFahMCARcwM= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:in-reply-to:message-id:mime-version:references :subject:to:x-sasl-enc:x-sasl-enc; s=smtpout; bh=u+8NDCtp2jaJp4I vtkuQRUJEMAc=; b=CudGPzPm5yJ2UOA+Y0hb+hpzyAkl2VcJJocfp2OTlMJrd4A Khsf2jGGrCIFPQ2/0ahEuuF3uB7DUVDx42MhmJb/v8eL0hzRENbFjpTtnE5jxwB1 qdH5eeEowQ+T3AaJnZOwX81ovKt8LLjyKr7yAEUapC3Rk0BgUJiWIsc4+wp8= X-Sasl-enc: LkL/aehxlkRHccbFbD80PIyJrsTzf3eYWjP5kp56XrI+ 1458574842 Received: from [192.168.1.2] (174-24-160-10.tukw.qwest.net [174.24.160.10]) by mail.messagingengine.com (Postfix) with ESMTPA id 994DEC0001A; Mon, 21 Mar 2016 11:40:42 -0400 (EDT) Subject: Re: [SQL] plan not correct? To: Bert References: <56F0079D.9060108@aklaver.com> <56F00CCF.9070702@aklaver.com> Cc: pgsql-general From: Adrian Klaver Message-ID: <56F015F9.7000808@aklaver.com> Date: Mon, 21 Mar 2016 08:40:41 -0700 User-Agent: Mozilla/5.0 (X11; Linux i686; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Pg-Spam-Score: -2.7 (--) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-general Precedence: bulk Sender: pgsql-general-owner@postgresql.org On 03/21/2016 08:29 AM, Bert wrote: My mistake, Cced wrong list. > That is easy to check. > > Let's do the same test again: > # select count(1) from dlp.st_itemseat; > count > ------- > 12 > (1 row) > > # select count(1) from loaddlp.st_itemseat_insert; > count > ------- > 87 --> of which 12 are already in the dlp.st_itemseat table > (1 row) > > # explain analyze * > QUERY PLAN > ----------------------------------------------------------------------------------------------------------------------------------------------------------------- > Insert on st_itemseat (cost=55.47..69.97 rows=150 width=228) (actual > time=2.345..2.345 rows=0 loops=1) > CTE upsert > -> Update on st_itemseat et (cost=17.50..55.42 rows=2 width=240) > (actual time=0.493..0.545 rows=12 loops=1) > -> Hash Join (cost=17.50..55.42 rows=2 width=240) (actual > time=0.303..0.318 rows=12 loops=1) > Hash Cond: ((et.tick_server_id = > st_itemseat_insert_1.tick_server_id) AND (et.itemseat_id = > st_itemseat_insert_1.itemseat_id)) > -> Seq Scan on st_itemseat et (cost=0.00..13.10 > rows=310 width=14) (actual time=0.025..0.028 rows=12 loops=1) > -> Hash (cost=13.00..13.00 rows=300 width=234) > (actual time=0.244..0.244 rows=87 loops=1) > Buckets: 1024 Batches: 1 Memory Usage: 13kB > -> Seq Scan on st_itemseat_insert > st_itemseat_insert_1 (cost=0.00..13.00 rows=300 width=234) (actual > time=0.005..0.120 rows=87 loops=1) > -> Seq Scan on st_itemseat_insert (cost=0.04..14.54 rows=150 > width=228) (actual time=0.637..0.726 rows=75 loops=1) > Filter: (NOT (hashed SubPlan 2)) > Rows Removed by Filter: 12 > SubPlan 2 > -> CTE Scan on upsert (cost=0.00..0.04 rows=2 width=8) > (actual time=0.498..0.561 rows=12 loops=1) > Planning time: 1.122 ms > Execution time: 2.682 ms > > # * > INSERT 0 0 > > # select count(1) from dlp.st_itemseat; > count > ------- > 87 > (1 row) > > > * the upsert query can be found attached to the first mail, but the > difference is that the 'where loadtabletime' is removed > > As you can see the in the update part of the explain the 'rows' nr is > 12. Which is what is expected. > But the rows on the insert are again 0, while it should be 75. > > wkr, > Bert > > On Mon, Mar 21, 2016 at 4:01 PM, Adrian Klaver > > wrote: > > On 03/21/2016 07:54 AM, Bert wrote: > > Ccing list > > Hello Ardian, > > The PostgreSQL version is 9.4.5 > > The reason I have the 'returning' statement in the update section is > because I only insert the data that has not been updated. I > don't see > why I would need to return anything in the insert section? > > > Well it was more about what you saw as the result of the UPDATE. It > is not clear to me whether that is 'UPDATE count' or the rows from > RETURNING? > > > On Mon, Mar 21, 2016 at 3:39 PM, Adrian Klaver > > >> wrote: > > On 03/21/2016 07:03 AM, Bert wrote: > > Dear all, > > I am not sure if I am looking at a bug, or I am just doing > something wrong. > Anyhow, to me it seems that the plan for an upsert is > wrong. (I > can not > find how many rows are inserted in the table) > > Regard the following setup: > # select count(1) from dlp.st_itemseat; > count > ------- > 0 > (1 row) > > # select count(1) from loaddlp.st_itemseat_insert where > loadtabletime = > '2016-03-21 14:53:28.771467'; > count > ------- > 12 > (1 row) > > # explain analyze * > > QUERY PLAN > > --------------------------------------------------------------------------------------------------------------------------------------------------------- > Insert on st_itemseat (cost=26.14..41.39 rows=1 > width=228) > (actual > time=1.282..1.282 rows=0 loops=1) > CTE upsert > -> Update on st_itemseat et (cost=0.15..26.11 > rows=1 > width=240) > (actual time=0.066..0.066 rows=0 loops=1) > -> Nested Loop (cost=0.15..26.11 rows=1 > width=240) (actual > time=0.061..0.061 rows=0 loops=1) > -> Seq Scan on st_itemseat_insert > st_itemseat_insert_1 (cost=0.00..13.75 rows=2 > width=234) (actual > time=0.031..0.040 rows=12 loops=1) > Filter: (loadtabletime = > '2016-03-21 > 14:53:28.771467'::timestamp without time zone) > Rows Removed by Filter: 75 > -> Index Scan using pk_st_itemseat on > st_itemseat et > (cost=0.15..6.17 rows=1 width=14) (actual time=0.001..0.001 > rows=0 loops=12) > Index Cond: ((tick_server_id = > st_itemseat_insert_1.tick_server_id) AND (itemseat_id = > st_itemseat_insert_1.itemseat_id)) > -> Seq Scan on st_itemseat_insert > (cost=0.02..15.27 rows=1 > width=228) (actual time=0.175..0.201 rows=12 loops=1) > Filter: ((loadtabletime = '2016-03-21 > 14:53:28.771467'::timestamp without time zone) AND (NOT > (hashed > SubPlan 2))) > Rows Removed by Filter: 75 > SubPlan 2 > -> CTE Scan on upsert (cost=0.00..0.02 > rows=1 > width=8) > (actual time=0.068..0.068 rows=0 loops=1) > Planning time: 1.022 ms > Execution time: 1.596 ms > (16 rows) > > > # * > INSERT 0 0 > > # select count(1) from dlp.st_itemseat; > count > ------- > 12 > (1 row) > > * the upsert query is added as an attachment to this mail. > > > In the query plan it seems that 0 rows are inserted; > although 12 > rows > are inserted when we compare the 2 counts. > When an update happens, the rows reported in the 'update' > statement are > correct. > > > Do you get a row count or the rows? > > The reason I ask is that in the UPDATE section you have > '...returning ET.*', but not in the INSERT section. > > Not sure if it matters in this case, but the Postgres > version might > provide context. > > > > Is this a bug? Or am I looking at the wrong part of the > plan? I > would > like to check how many rows are actually inserted from > the plan. > > wkr, > Bert > > -- > Bert Desmet > 0477/305361 > > > > > > -- > Adrian Klaver > adrian.klaver@aklaver.com > > > > > > > -- > Bert Desmet > 0477/305361 > > > > -- > Adrian Klaver > adrian.klaver@aklaver.com > > > > > -- > Bert Desmet > 0477/305361 -- Adrian Klaver adrian.klaver@aklaver.com -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general