asterixdb-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Mike Carey <dtab...@gmail.com>
Subject Re: Does Projection affect count() performance?
Date Sat, 01 Oct 2016 16:25:45 GMT
Sounds like there is a new materialization bug there.....  Please file a 
JIRA issue (and we'll need a query plan test case to keep it from 
breaking again).


On 10/1/16 2:01 AM, Wail Alkowaileet wrote:
> Hi,
>
> I know that early projections will enhance the performance.
> I just noticed something:
>
> 1- returning the whole tuple
> count( for $x in dataset Tweets
> return $x
> )
>
> => Throws an exception Java heap exceeded. (The heap-size is less than the
> sum of AsterixDB configured memory ... so it's not a problem).
>
> 2- However, returning one field
> count( for $x in dataset Tweets
> return $x.id
> )
>
> => Worked just fine.
>
> I'm just wondering, does the projection in count() affects its performance ?


Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message