Re: A better way than tweaking NTUP_PER_BUCKET - Mailing list pgsql-hackers

From Atri Sharma
Subject Re: A better way than tweaking NTUP_PER_BUCKET
Date
Msg-id CAOeZVif_hbmZ0yThvqwR=SoDrnedVE=jqjX209NqrTUFraikyg@mail.gmail.com
Whole thread Raw
In response to Re: A better way than tweaking NTUP_PER_BUCKET  (Jeff Janes <jeff.janes@gmail.com>)
Responses Re: A better way than tweaking NTUP_PER_BUCKET
List pgsql-hackers
Hi all,

I have been working on a patch for the above discussed
functionalities. I made an array of int32s, one for each bucket in a
hash table(the array is per hash table).

I am using the hash value directly to set the corresponding bit in the
bit field.Specifically:

bitfield_orvalue = 1<<hashvalue;
hashtable->bitFields[bucketNumber] =
(hashtable->bitFields[bucketNumber]) |bitfield_orvalue;

But,the hash values are way beyond this, and I admit that my choice of
int32 as bitfield isn't correct here.

The hash values are like:

13599104251359910425-1662820951-1662820951

What should I be using for the bit map?

Regards,

Atri

--
Regards,

Atri
l'apprenant



pgsql-hackers by date:

Previous
From: Kyotaro HORIGUCHI
Date:
Subject: Re: Reduce maximum error in tuples estimation after vacuum.
Next
From: Magnus Hagander
Date:
Subject: Re: [PATCH] Add an ldapoption to disable chasing LDAP referrals