From: Richard Wheeldon Newsgroups: comp.databases.oracle.misc Subject: Re: Determining a PK for a view Date: Wed, 06 Jun 2001 19:27:08 +0100 Message-ID: <3B1E75FC.15FB@rswheeldon.com> References: <3B1C2201.2781@rswheeldon.com> NNTP-Posting-Host: nova.rswheeldon.com X-NNTP-Posting-Host: nova.rswheeldon.com:62.49.142.69 X-Trace: news.demon.co.uk 991852490 nnrp-01:5303 NO-IDENT nova.rswheeldon.com:62.49.142.69 X-Complaints-To: abuse@demon.net X-Mailer: Mozilla 3.0Gold (X11; I; IRIX 6.2 IP22) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 30 Frank wrote: > "How can I automatically determine which columns in a "table like" object is > necessary to use in the WHERE > clause to uniquely find one single row in the object?" pretty much, yes. It seems the answer in general is there isn't a way :( > If it is a table you intend to use ROWID; be aware that ROWID for a given > row in a table may change during the lifetime of a table due to DBA's > reorganization, DELETE/INSERT, I was under the impression that insertions/deletions were unlikely to affect the rowid of another entry under normal circumstances. When will they change? Change due to an explicit DBA reorganization can be tolerated. > another approach to determine the columns is > to look in dba_col_constraints/dba_constraints to find possibly PK or UNIQUE > constraints. True. But this breaks down under in other circumstances, notably if these constraints are not explicitely defined. > For view I think it will be hard to automatically find the columns. Could > you try to use a namingstandard on the columns in the views that you need?? eg. Unfortunately, not. Richard