Re: Delaying the planning of unnamed statements until Bind - Mailing list pgsql-hackers

From Andrew Dunstan
Subject Re: Delaying the planning of unnamed statements until Bind
Date
Msg-id 40AE8CA3.1090105@dunslane.net
Whole thread Raw
In response to Re: Delaying the planning of unnamed statements until Bind  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers

Tom Lane wrote:

>Au contraire --- a full-table index scan can be vastly slower than a
>full-table seqscan.  I think it's wishful thinking to assume that
>picking an indexscan is the right thing when we don't know any better.
>
>  
>

I wish we could get this basic truth across to users somehow - I have 
lost count of the number of times I have had to explain that the 
crossover in cost between a sequential scan and an index scan occurs at 
a surprisingly low proportion of a table in most cases.

cheers

andrew



pgsql-hackers by date:

Previous
From: Tom Lane
Date:
Subject: Re: Delaying the planning of unnamed statements until Bind
Next
From: "Marc G. Fournier"
Date:
Subject: Re: Downloadable Mailing List Archives