>
> I'm a little unclear on what a "fact table" is. Can you explain?
Good question... The idea comes from data warehousing where a typical data
construction involves two "types" of table :
dimensions : time, location, ethicity....( essentially denormalized lookups )
facts : observations, accidents, sales ....
facts have a composite primary key , each componant of which is a foreign key
for one of the dimensions.
If drawn with the fact table(s) in the center and dimensions around about, then
the ERD looks like a "star". Hence the names "star schema" and "star query"
A quick search located a vaguely helpful page : ( apologies about the source )
http://www.oradoc.com/ora816/server.816/a76994/schemas.htm
A much better source is Kimball's book "The Data Warehousing Toolkit".
regards
Mark
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