Re: Help with sql-query

On Fri, 22 Jun 2007 03:54:05 -0700, Charles Hooper wrote:

> That is an interesting analysis. Five years ago, I might have made the
> same analysis about what is elegant and well designed. However, since
> that time I have had to deal with the aftermath of three, four... seven
> years of data collecting in such tables. Any idea what happens to the
> performsnce of the proposed CALENDAR table as three, four... seven years
> of dates are added, and for more than one CAL_NAME? Let's try a little
> experiment. Just to keep the numbers clean, we will insert 1000 dates
> into the CALENDAR table, which will carry us through a bit less than
> three years, even if one of those years happens to be a leap year.

Charles, this table is strongly recommended in Ralph Kimball's DW Toolkit book. I must say that I frequently use that "timetable" design. I have yet to see any problems with that design. Of course, the table must be appropriately structured and indexed. There is also a maintenance issue with the table, but it's nothing that cannot be easily solved by PL/SQL and Perl.

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