From: | Indraneel Majumdar <indraneel(at)www(dot)cdfd(dot)org(dot)in> |
---|---|
To: | Gerhard Dieringer <DieringG(at)eba-haus(dot)de> |
Cc: | pgsql-sql(at)postgresql(dot)org |
Subject: | Re: Antw: many-many mapping between unique tables |
Date: | 2000-10-16 20:13:56 |
Message-ID: | Pine.SGI.3.96.1001016130435.121309C-100000@www.cdfd.org.in |
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Lists: | pgsql-sql |
Yeah you understand the problem perfectly. The third table will definitely
contain unique entries if you take both x and y simultaneously. I wanted
some way of mapping where I would not need to repeat individual values of
x and y. I am not from a maths background and have absolutely no idea of
database design.
Is it possible to map the columns without repeating values?
\Indraneel
On Mon, 16 Oct 2000, Gerhard Dieringer wrote:
> I'm not sure if I understand your question. Is it right, that the x(i) are different values
> of an column x in table T1 and the y(i) are different values of an column y in table T2?
> And you want to have a n:m relation between the two tables?
> Then you need a third table T12 with columns x and y, that contains one row for each
> mapping of a x(i) with a y(j).
>
> I hope this helps.
>
>
> Gerhard
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