Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1sJpjC-006toH-UP for pgsql-admin@arkaria.postgresql.org; Wed, 19 Jun 2024 07:27:35 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.94.2) (envelope-from ) id 1sJpjA-00BS3j-Ne for pgsql-admin@arkaria.postgresql.org; Wed, 19 Jun 2024 07:27:33 +0000 Received: from makus.postgresql.org ([2001:4800:3e1:1::229]) by malur.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1sJpjA-00BS2P-Bx for pgsql-admin@lists.postgresql.org; Wed, 19 Jun 2024 07:27:33 +0000 Received: from mail-lj1-x22e.google.com ([2a00:1450:4864:20::22e]) by makus.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.94.2) (envelope-from ) id 1sJpj8-0022jT-On for pgsql-admin@postgresql.org; Wed, 19 Jun 2024 07:27:32 +0000 Received: by mail-lj1-x22e.google.com with SMTP id 38308e7fff4ca-2eaea28868dso85318441fa.3 for ; Wed, 19 Jun 2024 00:27:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cybertec-at.20230601.gappssmtp.com; s=20230601; t=1718782049; x=1719386849; darn=postgresql.org; h=mime-version:user-agent:content-transfer-encoding:autocrypt :references:in-reply-to:date:to:from:subject:message-id:from:to:cc :subject:date:message-id:reply-to; bh=BzkQERladmuCOxwKWmQiayxhdKGyVUmpVJqEaDjDO3w=; b=Y5CKe6eAotEvM5a8cQU8AXLgmxnh0QzSipzBGZ5gBIL/xNfC4CRWz9Vkxm9YMdsUQG NtYLFdtUJ8z0osfEmdBXaT7qtS6iaNbCpL/pFLtoXDl9H0TthDO87tXC8tE+aLfq9HTY VfMhxXeAkTrq5MLWpeAiBPO28T+pfXgaFL5VlGqEYrthV+/T+JD/7FlI5mCrbVvyH5/x xDX0hKcWNAS9lTwcn7Xohts8oZUUbWgVQhI3jI/mbmf3gaZvVNJO715HDNKCTR6V8PLz 6URKbzF6e8O7/kEODqRLUPrB124khYELT5v4NDaEVq+llvi/5c58dYYDjnggHI690X7Q KZSA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1718782049; x=1719386849; h=mime-version:user-agent:content-transfer-encoding:autocrypt :references:in-reply-to:date:to:from:subject:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=BzkQERladmuCOxwKWmQiayxhdKGyVUmpVJqEaDjDO3w=; b=WtbpFXVPFZ+CYSjgBdwLorTieq028Ojm6/5zM2PinXFY8yOkvNJH7qnd8G6CAXJ1Ya z78V8OTkIFz0mDsSB05OT3iELQGO+80YuaZJYARFkUnpTgsKvLWaRpqQIHBqbogMjS/5 KLWy+Q2BRhe2RlmAFrfQePl8qAIueLEtZ9iIOVwXHc2sMtlfEJa3gH79XnuQTCf80Nx2 p12SF8r46s114cEH7tEjXuTXJCicEfwwk46DcL81B85zd5tBZTleOarxbL4BvIfXQkO/ wP5ZbfOXj6GFnSaxxU94aJI1mYInTLrD3PFYjymMJec9vwN/DXF6ICRsvWjaci+SrFee wb9w== X-Forwarded-Encrypted: i=1; AJvYcCWCgnfy8lTA7hJD52Eym82/v9J/E/VxKzr/X6mUyN7pY3z9ueJpuKqXy0mT/T5cokBDb6hAeEcE20ZagIM5LuIUsMIOik+Wb2NjqA== X-Gm-Message-State: AOJu0YyGJ7W+DmDOZnc2KLj5vbGGl2EKYAiY3bAK8rycRqVed8WCWR0J lHY2E3RnnRll3wDRX/stRIu9hjfnAzu0eo7IKKcQCWGlVKVcLaA8yhGpe1FUoqg= X-Google-Smtp-Source: AGHT+IHfqeehaRhH3JQe+gOv9CQee+eBYAsy8DJ45TnNVBTavFB+7/zUmgbsaug1e8Kfsa96kR71lQ== X-Received: by 2002:a2e:2281:0:b0:2ec:3f29:a0ff with SMTP id 38308e7fff4ca-2ec3f29a25bmr6825501fa.31.1718782048656; Wed, 19 Jun 2024 00:27:28 -0700 (PDT) Received: from localhost.localdomain ([88.116.133.170]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-422f612800csm216211125e9.28.2024.06.19.00.27.27 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 19 Jun 2024 00:27:28 -0700 (PDT) Message-ID: <776e98bc5ded6b4cda83d1d5318f4186e4f8e344.camel@cybertec.at> Subject: Re: Materialized views & dead tuples From: Laurenz Albe To: Wells Oliver , pgsql-admin Date: Wed, 19 Jun 2024 09:27:27 +0200 In-Reply-To: References: Autocrypt: addr=laurenz.albe@cybertec.at; prefer-encrypt=mutual; keydata=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 bT5UrLvJ2jb99bA9QARzhFaxzyn0F/BUKzuIjRGNs/n6d5dNUFA0kOt8sX+TacmC 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 lDrT4wxdLJ/XCdbPPAyl+lZtOLsaHEEZvYNyTXwZc35dVf3R4/oz20HoG6s7ct8e1 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 36UMAx4ulWMyqJajLNGY0DdG8qIsR5nxRhrnK/mrCidZ8F9/D3bWAl4rjtHlsztN59 +AnW5l0HsQcY9ntFL/zEBOaonjdJf Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.50.4 (3.50.4-1.fc39) MIME-Version: 1.0 List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk On Tue, 2024-06-18 at 15:28 -0700, Wells Oliver wrote: > Apologies for the daft question, but I am surprised=C2=A0to see materiali= zed views > show=C2=A0up in pg_stat_user_tables with lots of dead tuples. These are r= ematerialized > nightly and, I thought, this had the effect of replacing/recreating them = anew. > Can someone shed some light on this? It makes a difference if you use REFRESH MATERIALIZED VIEW or REFRESH MATERIALIZED VIEW CONCURRENTLY. The first statement will just discard the materialized table and create it = anew, and you will never see a dead tuple. The second statement executes the query and updates the materialized table,= which can lead to dead tuples just like a normal UPDATE or DELETE. Yours, Laurenz Albe