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From: setas01@cai.com
Newsgroups: comp.databases
Subject: Re : Updatable Views
Message-ID: <330.26d1980a@cai.com>
Date: 21 Aug 90 20:22:34 GMT
Organization: Computer Associates International
Lines: 21

In one of the postings gordon@mead.UUCP (Gordon Edwards) writes:

> No one is questioning the ability to create a view containing a UNION.  Can
> the view be updated is the question.  

 My impression from the first posting was that some databases do not permit
 UNIONs in view definitions. 

> My previous post argues the case from a logical point of view.  To be
> updatable, the INSERT, UPDATE, and DELETE operations have to be defined.  If
> the view is created with a UNION, which table will a tuple be inserted?

 Yes, if the view consists of ONE table, CA-DB ** does ** permit an update.
 ( not if the view consists of more than one table ) I doubt if any vendor
 permits updateble views.
   
Ashok Sethi 

Standard Disclaimer :

" The views expressed are mine and not of my employer. "