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From: demasi@paisano.UUCP (Michael C. De Masi)
Newsgroups: comp.databases
Subject: Big fun w/Informix cursors.
Message-ID: <147@paisano.UUCP>
Date: Mon, 6-Jul-87 18:50:52 EDT
Article-I.D.: paisano.147
Posted: Mon Jul  6 18:50:52 1987
Date-Received: Wed, 8-Jul-87 04:40:35 EDT
Organization: AT&T Communications.  Fairfax, VA
Lines: 43
Keywords: Informix cursors stink

Hello people!

If any of you have seen these questions before, please bear with
me since I've been off the net for a while while the machine I was
on was going through some mental strain.

Basically, what I was wondering if I had missed something regarding
the cursor concept in Informix esql/c.  The first question involves
the use of the 'fetch' statement to advance the cursor through a
queried list of rows from a given declare statement.  Although fetch
does a fine job in the forward direction, there seems to be no way to
do what I would imagine would best be called an 'unfetch'.  Ie, is it
possible to back the cursor up a row (or more) to traverse already
fetched data? It would certainly seem to be a nice thing to be able to do,
and in fact is quite possible from the vanilla Informix generated screens.
Is this just the way the database is designed, or am I missing something
obvious?

The second question involves active lists queried down for update
purposes.  Again, one might query the set and advance through it
with fetch statements, but it seems that the first non-readonly activity
performed after the query (ie an insert, deletion or update) somehow
breaks the cursor making it impossible to use for any purpose.
Now maybe I can buy the fact that these cursors were meant to be
uni-directional, but am I to understand that they were designed to
be as fragile as I've stated?  Why bother to make it possible to
query multiple records for update when making one change to one 
record makes the whole query inoperative?

Again, it is entirely possible that I'm missing something wildly
obvious, and would greatly appreciate having my errors pointed out
to me in any format you'd like.  Also, if you've had the same problems,
please write and we can comiserate.

Great to be back on the net!
(By the way, the address is now paisan'o' instead of paisan'a'.
 And no, she didn't have a sex change, it's her brother, you pervert!)

-- 
Michael C. De Masi - AT&T Communications (For whom I work and not speak)
3702 Pender Drive, Fairfax, Virginia 22030   Phone: 703-246-9555
UUCP:   seismo!decuac!grebyn!paisano!demasi
     "Life.  Don't tell me about life." - Marvin, the paranoid android