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GROUP BY clause ignored in VIEWS with UNION Clause
Message
Information générale
Forum:
Visual FoxPro
Catégorie:
Base de données, Tables, Vues, Index et syntaxe SQL
Versions des environnements
Visual FoxPro:
VFP 9 SP1
OS:
Windows 7
Network:
Windows 2008 Server
Database:
Visual FoxPro
Application:
Desktop
Divers
Thread ID:
01575879
Message ID:
01575886
Vues:
41
See the same result in my View, if I use a TOP 1 statement in the 2nd View. Is there anyway around this in a View Definition (outside of creating a Temporary Table)?

>View definitions in VFP are independent of each other. If one view references another, the second view is executed and the result is used as if it were a table. Unless you include a GROUP BY in the second view, also, you wouldn't see grouped data. Keep in mind that a UNION contains an implicit DISTINCT operation which in turn does an implicit ORDER BY on every field. Compare the results of the following two queries to see what I mean:
>
>SELECT Type, id FROM SYS(2005)
>SELECT Type, id FROM SYS(2005) UNION SELECT Type, id FROM SYS(2005)
>
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