Skip site navigation (1) Skip section navigation (2)

Re: slow IN() clause for many cases

From: Joe Conway <mail(at)joeconway(dot)com>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: Simon Riggs <simon(at)2ndquadrant(dot)com>, andrew(at)supernews(dot)com, pgsql-hackers(at)postgresql(dot)org
Subject: Re: slow IN() clause for many cases
Date: 2005-11-29 22:39:12
Message-ID: (view raw, whole thread or download thread mbox)
Lists: pgsql-hackers
Tom Lane wrote:
> Simon Riggs <simon(at)2ndquadrant(dot)com> writes:
>>Do you think we'll be able to generate a single ScalarArrayOpExpr from a
>>small subselect and pass it through as an indexable expression?
> If you don't mind spelling it with the ARRAY(sub-select) syntax, which
> I think is a Postgres-ism (though it's possible Joe got it from
> SQL2003).

It's in SQL 2003. See excerpt below.


6.36 <array value constructor>


   Specify construction of an array.


   <array value constructor> ::=
     <array value constructor by enumeration> |
     <array value constructor by query>
   <array value constructor by enumeration> ::=
     ARRAY <left bracket or trigraph>
           <array element list>
           <right bracket or trigraph>
   <array value constructor by query> ::=
     ARRAY <left paren>
           <query expression> [ <order by clause> ]
           <right paren>

In response to

pgsql-hackers by date

Next:From: Simon RiggsDate: 2005-11-29 22:53:38
Subject: Re: slow IN() clause for many cases
Previous:From: Simon RiggsDate: 2005-11-29 22:23:05
Subject: Re: ice-broker scan thread

Privacy Policy | About PostgreSQL
Copyright © 1996-2017 The PostgreSQL Global Development Group