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db design to calculate overlap in group membership in time
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June 5th, 2010, 12:41 AM posted to microsoft.public.access.tablesdbdesign
Steve[_77_]
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Posts: 1,017
db design to calculate overlap in group membership in time
Hi Liz,
You ought to reconsider the tables I suggested. Multiple tables DOES NOT
make querying harder, In fact, multiple tab;es make querying easier. Data
entry will be easier and more accurate too!
Steve
"EHobs via AccessMonster.com" u60556@uwe wrote in message
news:a90abc7ad3805@uwe...
Hi Steve & Jeff,
Thanks for your comments. I was actually planning something much simpler
than
the several tables Steve posted - I am working with only one type of bird
at
one specific location. I was thinking of having just a single table that I
can query. I could put the data in the following format
Date BirdID ArrivalTime DepartureTime
Any ideas on how to structure a query that will allow me to:
1) determine the total shared amount of time present for any 2 individuals
2) determine all of the individuals present at any one time point
Thanks again,
Liz
Steve wrote:
Hi Liz,
Give me your comments please to the following tables ....
TblBirdType
BirdTypeID
BirdType (Robin, Sparrow, Dove, etc)
TblColor
ColorID
Color (Black, Red, B;ue, etc)
TblBird
BirdID
BirdTypeID
ColorID
other fields to uniquely identify a bird
TblLocation
LocationID
LocationDescription
other fields to iniquely identify a location
TblGroup
GroupID
LocationID
DateGroupObserved
TblGroupComposition
GroupCompositionID
GroupID
BirdID
TimeBirdObserved
ArrivalDeparture
Steve
Hi Steve,
[quoted text clipped - 66 lines]
Liz
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