Subject Fw: Performance
Author Leyne, Sean
In a message on the Borland b.p.i.general newsgroup "Jason Chapman
(JAC2)" <jason@...> wrote...

> I would use a blob or a separate table. You must consider what
happens when
> your query doe not use an index to locate all records required, e.g.
> * from myTable where thedate between xxxx and yyyy and someData =1
> where someData does not have an index. The engine will have to unpack
> of the records that fit into the date criteria into RAM and then
> them to see if somedata =1. I don't know how IB manages unpackeing
> from disk to RAM, but I wouldn't be surprised if it uses buffers that
> full width of the rows for speed. If this is the case, then you will
see a
> massive performance hit.

My question is:

Does the engine really unpack blobs which are not part of the select