Re: Fixing Performance issue with less selective columns

Thank you Mladen. I am not familiar with hash clusters. You mentioned cost vs benefit analysis to be done, so curious to know what is the negative side of having the hash cluster as opposed to the regular FBI index created on this normal table to cater this issue? I was trying to see if any docs stating the use cases of hash clusters to cater performance issues but not getting much on that on google. it would be great if you can point to some use cases. Thanks.

On Thu, Aug 26, 2021 at 8:34 AM Mladen Gogala <gogala.mladen_at_gmail.com> wrote:

> Well, if the database is an OLTP database, I would also consider
> creating a single table hash cluster. True, that would probably require
> quite a large reorganization of the table but only the OP can decide
> whether it's worth the effort or not. After all, such decisions are
> eventually made on the cost/benefit basis.
>
> On 8/25/21 2:14 PM, Lothar Flatz wrote:
> > This scenario cries for bitmap indexes.
> > Bitmap Indexes can deal with "not equal" as well as "is null".
>
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> Mladen Gogala
> Database Consultant
> Tel: (347) 321-1217
> https://dbwhisperer.wordpress.com
>
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