Thread: Cleanly cancel a query.

If I have a database running, and I see that
there is a postmaster process taking 99.9% cpu.

ie, a very large insert query.

Is there a way to cleanly shut down that query from the client or admin
side?


-Thanks

You can kill -TERM the postmaster that is executing the particular query.

cheers,
t.


On Fri, 8 Jun 2001, Dennis wrote:

> If I have a database running, and I see that
> there is a postmaster process taking 99.9% cpu.
>
> ie, a very large insert query.
>
> Is there a way to cleanly shut down that query from the client or admin
> side?
>
>
> -Thanks
>
> ---------------------------(end of broadcast)---------------------------
> TIP 4: Don't 'kill -9' the postmaster
>

To be more precise, if by "a very large insert" you mean an import of a large data file via COPY, then it is fully
transactionali.e. if you kill -TERM the corresponding postmaster, it'll be like the insert never took place. 
If you mean multiple INSERTs in a transaction block then again the same.
But if it is a text file with multiple INSERTs just by themselves, I'd guess killing the postmaster would live you with
atable only half-full. 

cheers,
thalis


On Fri, 8 Jun 2001, Thalis A. Kalfigopoulos wrote:

> You can kill -TERM the postmaster that is executing the particular query.
>
> cheers,
> t.
>
>
> On Fri, 8 Jun 2001, Dennis wrote:
>
> > If I have a database running, and I see that
> > there is a postmaster process taking 99.9% cpu.
> >
> > ie, a very large insert query.
> >
> > Is there a way to cleanly shut down that query from the client or admin
> > side?
> >
> >
> > -Thanks
> >
> > ---------------------------(end of broadcast)---------------------------
> > TIP 4: Don't 'kill -9' the postmaster
> >
>
>
> ---------------------------(end of broadcast)---------------------------
> TIP 3: if posting/reading through Usenet, please send an appropriate
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> message can get through to the mailing list cleanly
>

Dennis <dennis@zserve.com> writes:
> Is there a way to cleanly shut down that query from the client or admin
> side?

From the client: send a query-cancel request (for example, typing ^C
in psql usually does this).

From the admin: send a SIGINT to the backend running the query, which
has the same effect as a query-cancel request.

            regards, tom lane