Re: @ versus ~, redux

From: Gregory Stark <stark(at)enterprisedb(dot)com>
To: Matteo Beccati <php(at)beccati(dot)com>
Cc: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Andrew Dunstan <andrew(at)dunslane(dot)net>, pgsql-hackers(at)postgresql(dot)org, Oleg Bartunov <oleg(at)sai(dot)msu(dot)su>, Teodor Sigaev <teodor(at)sigaev(dot)ru>
Subject: Re: @ versus ~, redux
Date: 2006-09-04 10:05:34
Message-ID: 87wt8khrpt.fsf@enterprisedb.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Matteo Beccati <php(at)beccati(dot)com> writes:

> Tom Lane ha scritto:
>> OK, so if everyone is leaning to #3, the name game remains to be played.
>> Do we all agree on this:
>>
>> "x @> y" means "x contains y"
>> "x @< y" means "x is contained in y"
>>
>> Are we all prepared to sign a solemn oath to commit hara-kiri if we
>> invent a new datatype that gets this wrong? No? Maybe these still
>> aren't obvious enough.
>
> Does this mean that also contrib/ltree operators will likely change for
> consistency?
>
> ltree @> ltree
> - returns TRUE if left argument is an ancestor of right argument (or
> equal).
> ltree <@ ltree
> - returns TRUE if left argument is a descendant of right argument (or
> equal).

If you consider ltree entries to be sets containing all their children then
those sound consistent.

--
Gregory Stark
EnterpriseDB http://www.enterprisedb.com

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Robert Bernier 2006-09-04 10:22:35 Re: On Certification (was Re: [GENERAL] Thought provoking piece on NetBSD)
Previous Message Martijn van Oosterhout 2006-09-04 09:41:25 Re: Optimizing prepared statements