Sequential filtering in SQL

[Ruslan Zasukhin]

On 12/11/05 11:34 PM, "Ed Kleban" <Ed at Kleban.com> wrote:

Hi Ed,

> Ok Ruslan,
> 
> Time for a brand new topic.
> 
> I starting to work on the part of the design that will use the bit_and( x, y
> ) operator you have provided to allow me to do some masked filtering.  I
> need to apply multiple filters in multiple separate passes to take a big
> list and make it smaller and smaller with each filter pass until I have only
> the records I want remaining.
> 
> If bit_and were available as an API call, this would be very simple.
> I would simply do a Find to get a VSet, then do more Finds using the
> previous VSet result as an "inSet" argument for the next filter pass.

I think

Table Methods = Calculated fields is an answer.

You make some Method, setup its formula which return e.g. True/false
Do 

  set1 = fldMethod.FindValue( 1 )

Change method, and do next search.
This will be not indexed searches.

For super fast SEARCH you can have several methods which are indexed.
In other words, you have pre-calculation in your hands.

-- 
Best regards,

Ruslan Zasukhin
VP Engineering and New Technology
Paradigma Software, Inc

Valentina - Joining Worlds of Information
http://www.paradigmasoft.com

[I feel the need: the need for speed]