No thread isolation-- Unusual or Common?

Just had an experience in which a user attempted to run a very long SQL query. ("Long" in the sense that just to view the text of the query required about a dozen screens when looking at it with onstat) The SQL involved over 170 tables and UNION ALLs. However, the selectivity on each table was pretty high, though. In any event,. it used all the stack resources and crashed the server. This led me to ask tech support if there wasn't some way to limit resources used by each user session so that users are isolated. In other words, I wondered if there were some way to insulate users from each other so that an individual user couldn't crash the system with a rogue query. I was told that was not possible. Is this a common situation with other RDBMS's, or is Informix unusual? Just wondering. Thank you for any comments from folks experienced with other DBMS's. Regards, DG -- David Grove - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - "I think not," said Descartes, and disappeared.

On Tue, 6 May 2003 08:21:36 -0800, "David E. Grove" <david_grove@correct.state.ak.us> wrote: >Just had an experience in which a user attempted to run a very long SQL >query. ("Long" in the sense that just to view the text of the query >required about a dozen screens when looking at it with onstat) The SQL >involved over 170 tables and UNION ALLs. However, the selectivity on each >table was pretty high, though. In any event,. it used all the stack >resources and crashed the server. > >This led me to ask tech support if there wasn't some way to limit resources >used by each user session so that users are isolated. In other words, I >wondered if there were some way to insulate users from each other so that an >individual user couldn't crash the system with a rogue query. I was told >that was not possible. > >Is this a common situation with other RDBMS's, or is Informix unusual? Just >wondering. > >Thank you for any comments from folks experienced with other DBMS's. > >Regards, > >DG Which engine version is this?

9.21.FC4 on Solaris 8 "John Carlson" <john_carlson@whsmithusa.com> wrote in message news:ojufbv40aqghobtvicri61s67kiqg2m11r@4ax.com... > On Tue, 6 May 2003 08:21:36 -0800, "David E. Grove" > <david_grove@correct.state.ak.us> wrote: > > >Just had an experience in which a user attempted to run a very long SQL > >query. ("Long" in the sense that just to view the text of the query > >required about a dozen screens when looking at it with onstat) The SQL > >involved over 170 tables and UNION ALLs. However, the selectivity on each > >table was pretty high, though. In any event,. it used all the stack > >resources and crashed the server. > > > >This led me to ask tech support if there wasn't some way to limit resources > >used by each user session so that users are isolated. In other words, I > >wondered if there were some way to insulate users from each other so that an > >individual user couldn't crash the system with a rogue query. I was told > >that was not possible. > > > >Is this a common situation with other RDBMS's, or is Informix unusual? Just > >wondering. > > > >Thank you for any comments from folks experienced with other DBMS's. > > > >Regards, > > > >DG > > Which engine version is this?