if you want to put 1000 columns into one table, your data structure
needs some further investigation. you are trying to solve the wrong problem.
Regards,
Hans
Dilip Angal wrote:
> Hi
>
> I have a situation that I need flexible number columns to model the
> business requirements. It could go up to 1000 columns and will be a
> sparse matrix. One option I was considering was to have a table with
> col1......col1000
> Other option I can consider is store all of them as name values in
> single column as a string
>
> option 1
> col1 | col2 |col 3 |........|col56|.....|col77|
> 10 | 2 | | | 4 | | |
> 2 | | 4 | | |.... |6 |
>
> option 2
>
> "col1=10,col2=2,col56=4"
> "col1=2,col3=4,col77=6"
>
> I will have about 50Million such records in a table.
>
> I need to aggregate the column values for a given day by taking sum of
> all the rows
>
> "col1=12,col2=2,col3=4,col56=4,col77=6"
>
> Second option looks very elegant but aggregation is hard
> Besides, second option may have performance penalty (Especially when you
> have 50 Million records)
>
> Any one can give any pointers or comments on how to model this an how to
> aggregate it?
>
> Thanks
> Dilip
>
>
--
Cybertec Geschwinde u Schoenig
Schoengrabern 134, A-2020 Hollabrunn, Austria
Tel: +43/2952/30706 or +43/664/233 90 75
www.cybertec.at, www.postgresql.at, kernel.cybertec.at