[comp.databases] Aborting INGRES queries gracefully from ESQL/C

mjb@otter.hpl.hp.com (Michael Bright) (05/17/91)

I have a question about the best way to abort an INGRES query.
I am running an ESQL/C application on an HP 9000/300 series
workstation with Ingres release 6.3.

I am accessing the results using cursors.
I do not have access to 6.3's resource control.

1. How does ISQL act when it receives a control C from the keyboard?
  This is the functionality that I would like - i.e. that in the event of
  some exception condition I can abort the query without aborting the
  unix process which launched the query.
  Is there some proprietary protocol which it uses to communicate with
  the 'dbms' process?

  Is this a method I could use?

2. Is there a graceful way to abort a query from within ESQL/C.

3. Resource control:
  How do QUERY_IO_LIMIT work?
  Does it use the QEP to abort the query because the IO_LIMIT would be
  exceeded or does it abort if the LIMIT is actually reached.

  Presumably QUERY_ROW_LIMIT will only cause an abort after the ROW_LIMIT is
  actually reached.

Cheers,
Mike.

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