Cost of Blob Fields on Pdox Tables

Marcelo Rodrigues

Delphi Developer

Sun, 16 Oct 2005 20:33:57 GMT

Cost of Blob Fields on Pdox Tables

Hi,

I'm building an app that needs to store pictures. Since I'd never had to do
such an app I was wondering how the use of Blob fields will affect speed and
size.

Does anyone know something about it or where I can get more info on this
issue?

thanks
Marcelo

Bill Tod

Delphi Developer

Sun, 16 Oct 2005 20:59:56 GMT

Re:Cost of Blob Fields on Pdox Tables

Blobs affect speed since they add a lot more data that has to be read
across the network. If you only need the blobs some of the time you
can put them in a separate table. If you query and do not select the
blob field there is no impact. The effect on size is obvious.

--
Bill (TeamB)
(TeamB cannot respond to questions received via email)

Marcelo Rodrigue

Delphi Developer

Sun, 16 Oct 2005 21:12:58 GMT

Re:Cost of Blob Fields on Pdox Tables

Thanks,
Marcelo

"Bill Todd" <b...@notthis.dbginc.com> escreveu na mensagem
news:j3ivav080ctbf0nhletg2ng5350rqdu5on@4ax.com...

Quote

> Blobs affect speed since they add a lot more data that has to be read
> across the network. If you only need the blobs some of the time you
> can put them in a separate table. If you query and do not select the
> blob field there is no impact. The effect on size is obvious.

> --
> Bill (TeamB)
> (TeamB cannot respond to questions received via email)

heiko Luettg

Delphi Developer

Mon, 17 Oct 2005 14:52:35 GMT

Re:Cost of Blob Fields on Pdox Tables

Paradox has some ugly bugs with blob fields (same problems with indices).
If a blob field is damaged, you have to delete the whole record to "correct"
this.

So have MUST use a separat table if you do not wanna loose data.

Heiko

PS: I converted my app the interbase last year -> problems are gone.

Other Threads

1. Creating Pdox table with autoinc field as key field

2. Problems saving a stringlist to a BLOB field in PDOX

3. Change table type Pdox 4 to Pdox 7

4. MODIFY/ADD FIELD TO PDOX TABLE WITH DELPHI

5. Insert Query and Integer fields (Pdox Table)

6. Deleting graphic field in PDox table

7. Q: What is the Binary field in a Pdox table used to

8. Calculated Field Problem. Delphi w/ Pdox 4.5 Table

9. TBlobStream and Graphics field in PDOX table

10. Problem, Adding a new field to pdox table