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Returning output parameters</A> </FONT> </td>
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<h1>Returning Output Parameters</h1>
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<p>If stored procedure does not generate result
set(s) you can reach output parameters immediately after calling <A href="../OnLineDoc/Command_Execute.html" >SACommand::Execute</A>:</p>
<p><STRONG><FONT face=System
size=2>printf("%d\n",
cmd.Param("nOutput").asLong());</FONT></STRONG> </p>
<P>You can use <A
href="../OnLineDoc/Param.html" ><STRONG>SAParam</A> operators</STRONG> for quick accessing values. In this case you can process the result as shown below:</P>
<P><STRONG><FONT face=System size=2>long out_param =
cmd.Param("nOutput");<BR>
printf("%d\n",
out_param);</FONT></STRONG> </P>
<p>After the statement has been executed,
SQLAPI++ stores the returned values of output parameters in the <A
href="../OnLineDoc/Param.html">SAParam</A>
objects bound to those
parameters. On some servers these returned
values are not guaranteed to be set until all results returned
by the procedure have been fetched (using <A href="../OnLineDoc/Command_FetchNext.html" >SACommand::FetchNext</A>
method). See <A href="../ServerSpecific/index.html">Server specific
information</A> on output parameters availability on different
DBMSs.</p>
<P>For processing result set(s) (if any) see <A href="fetch.html" >Fetching result
set</A>
and <A href="fetch_multiple.html" >Fetching
multiple result sets</A>.</P>
<P>If you call a function SQLAPI++ Library
automatically creates <A href="../OnLineDoc/Param.html" >SAParam</A> object to
represent the function return value. You can refer to this <A href="../OnLineDoc/Param.html" >SAParam</A> object using SQLAPI++ predefined
name <STRONG>"RETURN_VALUE"</STRONG>.</P>
<P>Returning Long, BLob and CLob data can have some differences (if you
need piecewise operations) from other data types. <FONT
color=black face="">See <A href="blobs.html">Working with Long or
Lob(CLob, BLob) Data</A> to get more information.</FONT></P>
<H3>Problems and Questions</H3>
<P>If you don't find the answer to you questions or have some problems on
using the Library, please, send e-mail to <A
href="mailto:howto@sqlapi.com">howto@sqlapi.com</A>. </P>
<P> </P>
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