Search Postgresql Archives

Re: Window functions can't be used as LIMIT/FETCH FIRST alternative

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Subject: Re: Window functions can't be used as LIMIT/FETCH FIRST alternative
From: "David G. Johnston" <david.g.johnston@xxxxxxxxx>
Date: Sat, 20 May 2017 09:37:53 -0700
Arc-authentication-results: i=1; mx.google.com; dkim=pass header.i=@gmail.com; spf=pass (google.com: best guess record for domain of pgsql-general-owner+m231041=spinic=gmail.com@xxxxxxxxxxxxxx designates 2a02:16a8:dc51::56 as permitted sender) smtp.mailfrom=pgsql-general-owner+M231041=spinic=gmail.com@xxxxxxxxxxxxxx; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=gmail.com
Arc-message-signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=sender:precedence:list-unsubscribe:list-subscribe:list-post :list-owner:list-id:list-help:list-archive:cc:to:subject:message-id :date:from:references:in-reply-to:mime-version:dkim-signature :arc-authentication-results; bh=ORmgkJZqhwiAkro21RL1N8scjv8B11GCgl0/pjl7AhY=; b=O3tss/RL2CBnL4qGeIrdQ/1r6W8m4C/UyUzyJz0wKb5u0yu6kXmmmFamz8PVbIa5Pg EEwUb8F83+8hxPjxIK8h5IZazpOjblDKgIoxue8lgHanJJQOwtT6xhpZiJ4XhUitJpjV 51JvhIZaLFKsdchXu+K1I5mUGNQB6pQHTMgpWUbNoFW5N0BornxgpDBmiGb9Uu8C6Tx/ CFUkBDYD42v5Oe/ClymlKbsUGkqP+xdg/pngbqbuLefSDwuyACzKg1Rh9t/Z5Rls/+xz AjxLGVKBl0l9TQjd8/diT2QKuKzvTrEKodDVNpZeoB9jNGH6YPQ8k5qpmjsOC8F697sC 2aqA==
Arc-seal: i=1; a=rsa-sha256; t=1495298327; cv=none; d=google.com; s=arc-20160816; b=W3RGEcKc1vaSSKml9Ych9oSLYPcsw38fPtXgUkd9wPTvM7TzOiBJdq/QgfulglQC/d 7a/51WRN7HpaJtB7lE36bNhlonWWXk+K3efpSF8v1Hn5z3Xzv8Jgoo5C0iteWkzxReuU BcMLdfl8HEF5IkcbnkisuWSmB0jNS+4vyBBlaGFUYCvUVPe0Qv6hVlRYURHOkeLbIwfr C39HGqYnxRUYIZbgHxVhldzpSZhuhCtpKUgJTV66XFAsn6D1PrPjPgjZ5iopMNSVyT3x YpjwYsUIt0Oe9tHrPLYNwbpnrcOp/dTXcqgReNGqOaufxvJpn6wruF8jkhetV4Si5Qro 2uJg==
Cc: "pgsql-general@xxxxxxxxxxxxxx" <pgsql-general@xxxxxxxxxxxxxx>
In-reply-to: <465391495273833@web41g.yandex.ru>
References: <465391495273833@web41g.yandex.ru>

On Sat, May 20, 2017 at 2:50 AM, Navrotskiy Artem <bozaro@xxxxxxxxx> wrote:

This is especially unpleasant for expressions using RANK and DENSE_RANK, which can not simply be rewritten using LIMIT.

They cannot anyway, at least not DENSE_RANK with ties.

Others will have to speak to the dynamics involved with the overall current behavior.

David J.

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

References:
- Window functions can't be used as LIMIT/FETCH FIRST alternative
  - From: Navrotskiy Artem

Prev by Date: Window functions can't be used as LIMIT/FETCH FIRST alternative
Next by Date: Re: Partitioned Data and Locking
Previous by thread: Window functions can't be used as LIMIT/FETCH FIRST alternative
Index(es):
- Date
- Thread

[Index of Archives] [Postgresql Jobs] [Postgresql Admin] [Postgresql Performance] [Linux Clusters] [PHP Home] [PHP on Windows] [Kernel Newbies] [PHP Classes] [PHP Books] [PHP Databases] [Postgresql & PHP] [Yosemite]