Albert, Alastair, and Steve,

Great information and suggestions.

Couple more questions?

1) Is a note field stored in .rb2 with the rest of the table or does it go
in rb4 like varchar?

2) I assume that the note field only uses disk space for the number of
characters entered unlike a text field where it is allocated whether used or
not. Is this true?

3) What happens if you have a broken pointer in the NOTE table? How do you
fix that? With R:Scope? Is this what you were referring to Steve?

Thanks

Steve

-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Sent: Wednesday, September 17, 2003 11:21 AM
To: [EMAIL PROTECTED]
Subject: [RBASE-L] - RE: Note Fields


Fixing broken pointers requires RScope to find the next row of data for the
table after the point where the broken pointer is found. To do that, RScope
looks for rows of equal length to the defined length of the table rows.
RScope cannot do this with note fields because the row length is variable.

There is a note table matching every table that needs note fields. This
table has the PK from the header and the note field only. If we assume 10
tables with note fields, after the redesign, there will be 20 tables. 

A further consideration is that a note field is up to 4,092 characters while
the maximum row length is 4,096 bytes, leaving room for a single integer
value at 4 bytes. This could mean more than one note field per table, or
more than one note table per master table. In this case, one should
carefully consider using varchar fields, which are stored in file 4. In this
case the row length of the master table is fixed. It also allows more than
4,092 characters to be stored.

Hope this thins the mud out a bit.

 
"Fogelson, Steve" <[EMAIL PROTECTED]> wrote:

>A while back I had asked about Text vs. Note fields.
>
>A few responses indicated that they keep all "note"s in a separate table.
>Evidently problems with broken pointers.
>
>I assume you design your DBs with a table for ALL notes. And all the other
>tables contain Note_ID fields where appropriate, that point to that note in
>the note table. Then use a view to read a row including the note.
>
>Are these assumptions correct?
>
>Could someone elaborate on this design and problems with broken pointers.
>How is this design strategy easier to fix broken pointers?
>
>Thanks
>
>Steve Fogelson
>Internet Commerce Solutions
>
>


-- 
Albert Berry
Full Time Consultant to
PSD Solutions
350 West Hubbard, Suite 210
Chicago, IL 60610
312-828-9253 Ext. 32


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