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Memo (or BLOB) Fields and querry speed??

Can any one tell me if having memo (or BLOB) fields in my tables will slow
query execution time.

The tables will be in MS SQL Server or Interbase and the fields in
question will be text fields.

To keep speed as fast as possible should I use long strings rather than
memos or have another table full of memo fields and a pointer to them in
my other table and only look up the memo fields when the user wants to???

Or is this needless because memos (or BLOBS) don't really slow things
down?

Any opinions would be appreciated.

Regards
C Fraser

 

Re:Memo (or BLOB) Fields and querry speed??


Quote
co...@rjhill.co.nz (C Fraser) wrote:
>Can any one tell me if having memo (or BLOB) fields in my tables will slow
>query execution time.

>The tables will be in MS SQL Server or Interbase and the fields in
>question will be text fields.

>To keep speed as fast as possible should I use long strings rather than
>memos or have another table full of memo fields and a pointer to them in
>my other table and only look up the memo fields when the user wants to???

In Interbase our experience has been that the presence of large text memo
fields (I work in the publishing industry) within a table definitely
effeect performance.  The magnitude of the impact depends on the specific
implementation.  Text Blobs {*word*190} TTable performance! TQueries seem to
be less sensitive, but only because you can limit the size of the
record/field set to the client.

As a basic policy, we design our databases with dedicated tables for text
Blobs.

Our experience with large VAR CHAR fields was the worst.  The BDE just
{*word*88}s on them, at least using NT/Interbase server w/WFWG Clients.

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