From: Martijn Tonies
Date: May 20 2006 10:38am
Subject: Re: Is This A Redundant Info Example?
List-Archive: http://lists.mysql.com/mysql/198140
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>It depends on what the data is being used for.  If you want to know
>what address an order was shipped to then you need the historical
>address info.  If all you need is the current customer address,
>because, say, you're sending out holiday cards, then you might not
>need to keep an old address.

Indeed.

>Martin's explanation didn't say anything about deleting the data.

Same here ;-)

>Your idea isn't a bad one, although I shy away from boolean flags
>because you have to be careful about the indexes for it.

Exactly, I dislike them as well.

One solution could be:

addresses
-customerID
-addresID

and in customers:
-CurrentAddressID

to keep the current active address.

Martijn Tonies
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-Sheeri

On 5/19/06, Jay Blanchard <jblanchard@stripped> wrote:
> [snip]
> > Well, one reason could be, for example, that the address changes
> > over time and they want to know what address the customer was
> > when the order was processed.
> [/snip]
>
> So you would delete an old customer address in favor of a new one? I
> would rather have an 'active/inactive' column with an accompanying date
> stamp.
>