The only problem is detecting that the data is identical in the first
place. If I have to do a select with 7 AND statements to see if I have
identical data, I'm going to take a huge performance hit. I was hoping
this had been done at a very low level, but it doesn't look like it.
Maybe it's just as unrealistic at a low level, but I could swear I had
heard of this feature before.
Oh well.
J
PS. I didn't mention this before, but a link table (ie a relational
structure) is not possible in my situation.
On Wednesday, August 29, 2001, at 01:47 PM, james wrote:
>
> Julian,
>
> I am not aware of any databases smart enough to decide to create
> references
> for rows whose data is identical to an existing row. If the duplicate
> data
> is creating resource issues, there's a couple things that you can do to
> eliminate the duplicate data. Probably the easiest would be, in the
> case of
> varchar data, to add a column for a row number. If the data to be
> inserted
> is identical to data in a row that's already in the database, an encoded
> reference to the row number of the row with the original data could be
> stored. That way, you're just storing the reference to the original
> data.
>
> Example:
>
> RowNum ProdNum Revision Description_varchar
> 455333 10 1
> XXXYYYXXXYYYXXXYYYXXXYYYZZZYYYYXXXX
> 873245 10 2 <<-455333->>
> 934532 10 3 <<-455333->>
>
> If you don't want to do the encoding thing, you could create a "link"
> table
> to accomplish the same thing.
>
> HTH,
> James Potts
>
>
> "Julian Wood" <[EMAIL PROTECTED]> wrote in message
> [EMAIL PROTECTED]">news:[EMAIL PROTECTED]...
>>
>> Hi,
>>
>> Don't know if this is the best place to ask, but I thought I would give
>> it a try.
>>
>> I was just wondering if anyone knows of any databases which deal with
>> data duplication (at a low level). Say I have two (or ten) identical
>> records, does anyone know of any databases which would only keep one
>> copy of the data and use references for the other records? Does this
>> work if 7 out of the 8 columns (for instance) are identical (ie the
>> primary key is different but everything else is identical). Do such
>> db's
>> exist? Or do they all do this? Or am I just dreaming?
>>
>> J
--
Julian Wood
Programmer/Analyst
University of Calgary
>
>
>
> --
> PHP General Mailing List (http://www.php.net/)
> To unsubscribe, e-mail: [EMAIL PROTECTED]
> For additional commands, e-mail: [EMAIL PROTECTED]
> To contact the list administrators, e-mail: [EMAIL PROTECTED]
>
