Re: Unknown SQL

In article <2CvR6.742$ma.178570354_at_radon.golden.net>, Bob Badour says...
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>Carl Rosenberger wrote in message <9f44gm$go2$03$1_at_news.t-online.com>...
>>What do you do, if two references to the same child are possible?
>
>"Child" is a network model or hierarchic model concept. If one relation has
>a constraint that at least one row must exist in two or more specified
>tables, I would suggest that the data model is poorly designed to begin
>with. Straw man.
>

If this is a typical many-to-many example like this:

table Students;
table Classes;
table Enrollments;

then whenever deleting a student we would probably want to cascade to Enrollments, even though this enrollment is "referenced" by some Class (not oo class, thanks god;-). David Cressey posted very good guidelines when we want to cascade delete in some old thread. Anyhow, there doesn't seem to be any logical problems associated with cascading deletes, as Carl suggested. Received on Thu May 31 2001 - 21:07:36 CEST