A Wednesday 16 September 2009 15:18:04 Vineet Jain escrigué:
> I have a table with two fields: date (str 8) and value (float32).
>
>
>
> I created two files and am trying to explain the file size difference
> between the two:
>
>
>
> File 1:
>
> 3 groups and 2 tables. Each table has 390 rows. Total number of rows: 780
>
>
>
> File 2:
>
> 3 groups and 102 tables. Each table has 7 rows. Total number of rows: 784
>
>
>
> File 2 is 1.3MB while file 1 is 43k.  In my design I was going to have
> 1000's of tables and hundred's of groups. Given the size difference between
> the two files, is it better to have few table with extra keys or a large
> number of smaller tables?

The difference is due to the fact that file 1 has to put much more metadata 
(i.e. data that describes data) in there, while in file 2 metadata is minimal.  
File 1 structure is always preferred over file 2 because it is more scalable.

Hope that helps,

-- 
Francesc Alted

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