Hi Maya,

> I am about to add a potentially very large blob field to one of my
> tables for the storing of images for stock items.
>
> My instinct would be to simply add the new blob field to the existing
> table which contains the stock data. What is worrying me though, is some
> users may have added a "select * from MasterTable where StockCode =
> :StockCode" dataset to their reports in order to pick up some stock
> info. There may be some serious speed degradation on reports where this
> has been done (I presume?).
>
>
>
> Also, when editing a stock record, if the large field was in a separate
> table, it would make it much easier to control the updating of the image
> separately and only when the image gets modified, without having to
> worry about locking issues.

Locking issues? Do you expect multiple people to run the same
UPDATE statement against the record?

> There will only ever be one image for each stock item, and images will
> never be shared amongst stock items.
>
>
>
> Would putting the blob in a separate table be considered good database
> design, or an atrocious big no-no?

SELECT * FROM ... is a big no-no. Better get that fixed :-)

Martijn Tonies
Database Workbench - tool for InterBase, Firebird, MySQL, NexusDB, Oracle &
MS SQL Server
Upscene Productions
http://www.upscene.com
My thoughts:
http://blog.upscene.com/martijn/
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