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><H1
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>WHENEVER</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN45841"
></A
><H2
>Name</H2
>WHENEVER&nbsp;--&nbsp;specify the action to be taken when an SQL statement causes a specific class condition to be raised</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN45844"
></A
><H2
>Synopsis</H2
><PRE
CLASS="SYNOPSIS"
>WHENEVER { NOT FOUND | SQLERROR | SQLWARNING } <TT
CLASS="REPLACEABLE"
><I
>action</I
></TT
></PRE
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN45847"
></A
><H2
>Description</H2
><P
>     Define a behavior which is called on the special cases (Rows not
     found, SQL warnings or errors) in the result of SQL execution.
    </P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN45850"
></A
><H2
>Parameters</H2
><P
>     See <A
HREF="ecpg-errors.html#ECPG-WHENEVER"
>Section 33.8.1</A
> for a description of the
     parameters.
    </P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN45854"
></A
><H2
>Examples</H2
><PRE
CLASS="PROGRAMLISTING"
>EXEC SQL WHENEVER NOT FOUND CONTINUE;
EXEC SQL WHENEVER NOT FOUND DO BREAK;
EXEC SQL WHENEVER SQLWARNING SQLPRINT;
EXEC SQL WHENEVER SQLWARNING DO warn();
EXEC SQL WHENEVER SQLERROR sqlprint;
EXEC SQL WHENEVER SQLERROR CALL print2();
EXEC SQL WHENEVER SQLERROR DO handle_error("select");
EXEC SQL WHENEVER SQLERROR DO sqlnotice(NULL, NONO);
EXEC SQL WHENEVER SQLERROR DO sqlprint();
EXEC SQL WHENEVER SQLERROR GOTO error_label;
EXEC SQL WHENEVER SQLERROR STOP;</PRE
><P
>     A typical application is the use of <TT
CLASS="LITERAL"
>WHENEVER NOT FOUND
     BREAK</TT
> to handle looping through result sets:
</P><PRE
CLASS="PROGRAMLISTING"
>int
main(void)
{
    EXEC SQL CONNECT TO testdb AS con1;
    EXEC SQL ALLOCATE DESCRIPTOR d;
    EXEC SQL DECLARE cur CURSOR FOR SELECT current_database(), 'hoge', 256;
    EXEC SQL OPEN cur;

    /* when end of result set reached, break out of while loop */
    EXEC SQL WHENEVER NOT FOUND DO BREAK;

    while (1)
    {
        EXEC SQL FETCH NEXT FROM cur INTO SQL DESCRIPTOR d;
        ...
    }

    EXEC SQL CLOSE cur;
    EXEC SQL COMMIT;

    EXEC SQL DEALLOCATE DESCRIPTOR d;
    EXEC SQL DISCONNECT ALL;

    return 0;
}</PRE
><P>
    </P
></DIV
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><A
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></A
><H2
>Compatibility</H2
><P
>     <TT
CLASS="COMMAND"
>WHENEVER</TT
> is specified in the SQL standard, but
     most of the actions are PostgreSQL extensions.
    </P
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