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Home -> Community -> Usenet -> comp.databases.theory -> Re: Implicit constraints in a view
If I may make a twist on the recent view discussions here and in the
other busy thread, I'd like to ask this question: what do the common SQL
products do in the following case?
Suppose we have S1 equal to an empty relation with heading {S#, SNAME} with S# as (candidate) key and S2 equal to the same relation and then we define view S as S1 UNION S2. Then we insert the value {'S1', 'X'} into S1 and the value {'S1', 'Y'} into S2. Then we select view S.
(I'm also curious if the SQL standard has anything to say about this.)
p Received on Thu Nov 09 2006 - 18:44:42 CST
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