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<H1 ALIGN=CENTER>OTL 4.0, Constant SQL statements</H1>
<H1><A NAME="otl_constant_sql"></A>Constant SQL statements</H1>
<P>A SQL statement / PL/SQL block / stored procedure call is considered
to be constant if it does not have any bind variables. OTL 4.0 has a static
(in class) function to execute constant statements. </P>
<P><B><FONT SIZE=+1>Examples (Oracle)</FONT></B> </P>
<PRE> otl_cursor::direct_exec
(db, // <A HREF="otl3_connect_class.htm">connect</A> object
"create table test_tab(f1 number, f2 varchar2(30))"
); // create table</PRE>
<PRE> otl_cursor::direct_exec
(db, // <A HREF="otl3_connect_class.htm">connect</A> object
"drop table test_tab", // SQL statement or PL/SQL block
<A HREF="otl3_exception_class.htm#enum">otl_exception::disabled</A> // disable OTL exceptions,
// in other words, ignore any
// database error
); // drop table</PRE>
<P><B><FONT SIZE=+1>Examples (ODBC, DB2-CLI)</FONT></B> </P>
<PRE> otl_cursor::direct_exec
(db, // <A HREF="otl3_connect_class.htm">connect</A> object
"create table test_tab(f1 numeric, f2 varchar(30))"
); // create table</PRE>
<PRE> otl_cursor::direct_exec
(db, // <A HREF="otl3_connect_class.htm">connect</A> object
"drop table test_tab", // SQL statement or stored procedure call
<A HREF="otl3_exception_class.htm#enum">otl_exception::disabled</A> // disable OTL exceptions,
// in other words, ignore any
// database error
); // drop table</PRE>
<P>otl_cursor is one of the OTL 4.0 internal classes. It is not recommended
to use the OTL 4.0 low level classes and functions except for the <I>direct_exec()</I>
because it is a special case and it will not be discontinued in the future
releases of the OTL. </P>
<P>The direct_exec() function may return the following values of the <I>long
int </I>datatype: </P>
<UL>
<LI><B>-1</B>, if otl_exceptions are disabled (the second parameter is
set to otl_exception::disabled) and the underlying API returns an error.</LI>
<LI><B>>=0</B>, if the SQL command to be executed is finished succesfully.
Actually, the function returns the <I>ROWS PROCESSED COUNT </I>(RPC)in
case of INSERT, UPDATE or DELETE statements.</LI>
</UL>
<P>Here is an example of the direct_exec(), returning a row processed count:
<BR>
</P>
<PRE> long rpc=otl_cursor::direct_exec
(db, // <A HREF="otl3_connect_class.htm">connect</A> object
"delete from test_tab where f1>=95"
);
cout<<"Rows deleted: "<<rpc<<endl;</PRE>
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