Re: How number of columns affects performance

On Fri, 2003-08-01 at 12:14, Francisco J Reyes wrote:
> On Fri, 1 Aug 2003, Ron Johnson wrote:
>
> > Do all 100 fields *really* all refer to the same *one* entity,
> > with no repeating values, etc?
>
> Yes all fields belong to the same entity. I used 100 as an example it may
> be something like 60 to 80 fields (there are two tables in question). I
> don't formally do 3rd normal form, but for the most part I do most of
> the general concepts of normalization.

Woo hoo!!

> Yes some of the fields are varchars. 5 fields are varchar(22) and 3 longer
> (35, 58, 70). The total row length is a little over 400 characters in
> Foxpro. In postgreSQL may be less than 300 (ie Foxpro uses ASCII
> representation for numbers so to store "1234567" it uses 7 bytes, whereas
> in PostgreSQL I can just make it an int and use 4 bytes)

But I'd only split if these big field are rarely used. Note that
VARCHAR(xx) removes trailing spaces, so that also is a factor.

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