On Tue, Mar 9, 2010 at 2:28 PM, Sylvain Lebresne <sylv...@yakaz.com> wrote:

> > A row causes a disk seek while columns are contiguous.  So if the row
> isn't
> > in the cache, you're being impaired by the seeks.  In general, fatter
> rows
> > should be more performant than skinny ones.
> Sure, I understand that. Still, I get 400 columns by seconds (ie, 400 seeks
> by
> seconds) when the rows only have one column by row, while I have 10 columns
> by seconds when the row have 100 columns, even though I read only the first
> column.

Doesn't that imply the disk is having to seek further for the rows with more


Reply via email to