Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.84_2) (envelope-from ) id 1bDGYR-00077f-Ha for pgsql-docs@arkaria.postgresql.org; Wed, 15 Jun 2016 19:32:47 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.84_2) (envelope-from ) id 1bDGYR-0005uq-1N for pgsql-docs@arkaria.postgresql.org; Wed, 15 Jun 2016 19:32:47 +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 1bDGYQ-0005tv-Bj for pgsql-docs@postgresql.org; Wed, 15 Jun 2016 19:32:46 +0000 Received: from mail-io0-x234.google.com ([2607:f8b0:4001:c06::234]) by makus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.84_2) (envelope-from ) id 1bDGYJ-0004Bc-5c for pgsql-docs@postgresql.org; Wed, 15 Jun 2016 19:32:45 +0000 Received: by mail-io0-x234.google.com with SMTP id n127so30540732iof.3 for ; Wed, 15 Jun 2016 12:32:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:from:date:message-id:subject:to; bh=NgDHlFeucoV47+YE0ZvvzhaMA9bogi6Ddc3xJMjSzOo=; b=d7ra0V0uumOdPxNyyv7fabVYCxAHywzsu1Syl6LIukBGCWjvQeppIbsXF5D5eH4Z6i A8XqDb9QTAHWaoB1kX1kHpgAp4/LxM6pVFdtj0NIcuOIAXQCf/4+3vrD8sahMaQ+/6Of GsGwm7O/rM4tdgECN10aR6Yrexdy5Ww3K4nptdvmiM4nnLLccSgjfcmVH/yP0rz3dcxC CEveAEAKfSUzvoeRG7GyzkvqY1BG25T3gPGRoHOIZpKOM8Lq3qFGnydFp+mQWktH3bhu jAypWUEuFFfu+QNmZ4a9eQ7jRDQiSBbXaIt4spN5Mcr8c6i2r7Proy7JQjAJSu1Oi9Bo n97w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=NgDHlFeucoV47+YE0ZvvzhaMA9bogi6Ddc3xJMjSzOo=; b=diE1UVZV6hzx0SWWJXN1gY8dbktg1HtdEQvgdxAEi1v/Fcpa80UgFqywcTbRjbi8rn NyU1rClfJSHSMDWZzSDHQu+laL4h3C0RplGRldU7IL0YsqpVXL2BxbL10Vtj8oWR6xwU yJcj7GC3qkKppbSWzNaMu3/25lcu+nfGXxha43umGc4xLN3o30Zqrb/q3wCacHBDlkxj aWE/AGCMce+0LLvkjnsAPvGbxI2nLZNhSUFOd/FRj/PoeyrapBcV4F/4O30tCYlYsebz m13Frjgi5S4VvIUNnfEG2mxVqCyr2gfeTGPcQuSxUC/Mu6dWyovvX12+5Daz5MJpNsfd K4WA== X-Gm-Message-State: ALyK8tJuLgaBf8r2k7tIDdBvvCp9+kUEJR5H7mP76Fk1QG7Z62nLlFWKnXev+OPdG6Ag84+vn4EE1m45MUo08Q== X-Received: by 10.157.23.232 with SMTP id j95mr194592otj.109.1466019158010; Wed, 15 Jun 2016 12:32:38 -0700 (PDT) MIME-Version: 1.0 Received: by 10.157.34.104 with HTTP; Wed, 15 Jun 2016 12:32:37 -0700 (PDT) From: "David G. Johnston" Date: Wed, 15 Jun 2016 15:32:37 -0400 Message-ID: Subject: Clarification of "void" type To: "pgsql-docs@postgresql.org" Content-Type: multipart/alternative; boundary=94eb2c09ae1a25b3590535562f7c X-Pg-Spam-Score: -2.7 (--) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-docs Precedence: bulk Sender: pgsql-docs-owner@postgresql.org --94eb2c09ae1a25b3590535562f7c Content-Type: text/plain; charset=UTF-8 The section on pseudo-types names "void" and describes is thusly: """ Indicates that a function returns no value. """ This can be reasonably interpreted to mean: "Use this when you don't want the execution of a function to return a value." (i.e., the empty set) The following paragraph, suitably marked up, would be a nice addition: If a function declares "RETURNS void" the result of executing the function will be a single row and column whose type pg_typeof() returns "void". Void is not null and typically displays textually as the empty string. I'd maybe modify the table to read: void : A value that has no content: used to indicate that a function returns no value. https://www.postgresql.org/docs/devel/static/datatype-pseudo.html David J. --94eb2c09ae1a25b3590535562f7c Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
The section on pseudo-types names "void" and = describes is thusly:

"""
"&quo= t;"

This can be reasonably interpreted to mean: = =C2=A0"Use this when you don't want the execution of a function to= return a value." (i.e., the empty set)

The fol= lowing paragraph, suitably marked up, would be a nice addition:
If a function declares "RETURNS void" the result of exe= cuting the function will be a single row and column whose type pg_typeof() = returns "void".=C2=A0 Void is not null and typically displays tex= tually as the empty string.

I'd maybe modify the t= able to read:

void : A value that has no content: used= to indicate that a function returns no value.

<= a href=3D"https://www.postgresql.org/docs/devel/static/datatype-pseudo.html= ">https://www.postgresql.org/docs/devel/static/datatype-pseudo.html

David J.

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