Senin, 30 April 2012

RE: [MS_AccessPros] table design

 

Elizabeth-

Better to properly normalize the design. Putting a string of date fields in the
Client table would violate first normal form (repeating groups).

John Viescas, author
Microsoft Office Access 2010 Inside Out
Microsoft Office Access 2007 Inside Out
Building Microsoft Access Applications
Microsoft Office Access 2003 Inside Out
SQL Queries for Mere Mortals
http://www.viescas.com/
(Paris, France)

-----------------------------

From: MS_Access_Professionals@yahoogroups.com
[mailto:MS_Access_Professionals@yahoogroups.com] On Behalf Of glcass58
Sent: Monday, April 30, 2012 9:14 PM
To: MS_Access_Professionals@yahoogroups.com
Subject: Re: [MS_AccessPros] table design

 
Yes, my question is on the attributes. Is it better to have a narrow table of
client_id and client name with one to one relationships by client_id to many
subject-matter attribute tables? Or is it better to have one wide attribute
table? thanks

--- In MS_Access_Professionals@yahoogroups.com, John Viescas <JohnV@...> wrote:
>
> Elizabeth-
>
> So the related table is Client? That should give you a 1-M relationship to
this
> table as long as you include ClientID. Each client will have multiple events
> consisting of an EventID and the date the event occurred.
>
> John Viescas, author
> Microsoft Office Access 2010 Inside Out
> Microsoft Office Access 2007 Inside Out
> Building Microsoft Access Applications
> Microsoft Office Access 2003 Inside Out
> SQL Queries for Mere Mortals
> http://www.viescas.com/
> (Paris, France)
>
> ---------------------------------
>
> From: MS_Access_Professionals@yahoogroups.com
> [mailto:MS_Access_Professionals@yahoogroups.com] On Behalf Of glcass58
> Sent: Monday, April 30, 2012 8:45 PM
> To: MS_Access_Professionals@yahoogroups.com
> Subject: Re: [MS_AccessPros] table design
>
>  
> The dates are when forms are sent to clients and received back from clients. I
> was going to have them in one table
> ID
> Event_ID (key to the event description, i.e. Form "A" Sent Date)
> Date
>
> The attributes are about the client. Do you need more info? Thanks for your
> help.
>
> --- In MS_Access_Professionals@yahoogroups.com, John Viescas <JohnV@> wrote:
> >
> > Elizabeth-
> >
> > Need more info. What are these "dates" related to? Why aren't they in their
> > related table(s)? One-one joins are a pain the patootie.
> >
> > John Viescas, author
> > Microsoft Office Access 2010 Inside Out
> > Microsoft Office Access 2007 Inside Out
> > Building Microsoft Access Applications
> > Microsoft Office Access 2003 Inside Out
> > SQL Queries for Mere Mortals
> > http://www.viescas.com/
> > (Paris, France)
> >
> > -----------------------------
> >
> > From: MS_Access_Professionals@yahoogroups.com
> > [mailto:MS_Access_Professionals@yahoogroups.com] On Behalf Of glcass58
> > Sent: Monday, April 30, 2012 5:36 PM
> > To: MS_Access_Professionals@yahoogroups.com
> > Subject: [MS_AccessPros] table design
> >
> >  
> > Hi there-
> >
> > I have many, many attributes and a factless fact table (dates of events). My
> > first thought is that I'd like to put the attributes in separate tables by
> > subject matter and have one to one joins. But then I thought I better ask
you
> > all if you thought Access would run faster if the attributes were in one
wide
> > table.
> >
> > Thanks,
> > Elizabeth
> >
>

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