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NAME="PG-CANCELREQUEST"
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>pg_cancelrequest</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN1914"
></A
><H2
>Name</H2
>pg_cancelrequest -- Cancel an in-progress asynchronous query</DIV
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><A
NAME="AEN1917"
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><H2
>Synopsis</H2
><PRE
CLASS="SYNOPSIS"
>pg_cancelrequest <VAR
CLASS="PARAMETER"
>conn</VAR
></PRE
></DIV
><DIV
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><A
NAME="AEN1920"
></A
><H2
>Description</H2
><P
><CODE
CLASS="FUNCTION"
>pg_cancelrequest</CODE
> asks the database server to
abandon processing of the current command issued by
<A
HREF="pg-sendquery.html"
>pg_sendquery</A
>.
</P
></DIV
><DIV
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><A
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></A
><H2
>Arguments</H2
><P
></P
><DIV
CLASS="VARIABLELIST"
><DL
><DT
><VAR
CLASS="REPLACEABLE"
>conn</VAR
></DT
><DD
><P
> The handle of the connection on which to cancel the current command.
</P
></DD
></DL
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN1933"
></A
><H2
>Return Value</H2
><P
> Nothing. Throws a Tcl error if an error occurs.
</P
></DIV
><DIV
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><A
NAME="AEN1936"
></A
><H2
>Notes</H2
><P
>There is no guarantee that the command will actually be canceled. For
example, the command may have been completed before the database server
can receive and handle the cancel request. If a request is canceled, and
you were in the middle of a transaction, the entire transaction is rolled
back.
</P
><P
>You still need to call <A
HREF="pg-getresult.html"
>pg_getresult</A
> repeatedly until it
doesn't return anything, and deal with all the returned result handles,
usually by freeing them with <TT
CLASS="LITERAL"
>pg_result -clear</TT
>.
</P
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>Caution</B
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><P
>This command is part of a new Tcl interface to asynchronous query
processing capabilities, and should be considered experimental.
The command may change and backwards compatibility is not assured.
</P
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