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<p>
This example works with Oracle 8.x and SQL Server 6.5/7.0 without any
modifications to the table structure or datatypes.
</p>



<h4>Source code</h4>
<pre>

<font color="#FF0000">#include &lt;iostream.h&gt;</font>
<font color="#FF0000">#include &lt;stdio.h&gt;</font>
<font color="#FF0000">#include &lt;otl.h&gt;</font>

<a href="#ref002">otl_connect</a> db; <i><font color="#804000">// connect object</font></i>

<a name="ref301"></a><h4><font color="#0000A0">void</font> insert()</h4>
<i><font color="#804000">// insert rows into table</font></i>
{ 
 <a href="#ref001">otl_stream</a> o(50, <i><font color="#804000">// buffer size</font></i>
	      <font color="#008080">"insert into test_tab values(:1&lt;int&gt;,:2&lt;char[31]&gt;)"</font>, 
	         <i><font color="#804000">// SQL statement</font></i>
	      db <i><font color="#804000">// connect object</font></i>
	     );
 <font color="#0000A0">char</font> tmp[32];

 <font color="#0000A0">for</font>(<font color="#0000A0">int</font> i=1;i&lt;=100;++i){
  sprintf(tmp,<font color="#008080">"Name%d"</font>,i);
  o.<a href="#ref011">printf</a>(<font color="#008080">"%d %s"</font>,i,tmp); <i><font color="#804000">// write one row into stream</font></i>
 }
}

<a name="ref302"></a><h4><font color="#0000A0">void</font> select()</h4>
{ 
 <a href="#ref001">otl_stream</a> i(50, <i><font color="#804000">// buffer size</font></i>
	      <font color="#008080">"select * from test_tab where f1&gt;=:1&lt;int&gt; and f1&lt;=:2&lt;int&gt;*2"</font>,
	         <i><font color="#804000">// SELECT statement</font></i>
	      db <i><font color="#804000">// connect object</font></i>
	     ); 
   <i><font color="#804000">// create select stream</font></i>
 
 <font color="#0000A0">int</font> f1;
 <font color="#0000A0">char</font> f2[31];

 i<a href="#ref003">&lt;&lt;</a>8<a href="#ref003">&lt;&lt;</a>8; <i><font color="#804000">// assigning :1 = 8, :2 = 8</font></i>
   <i><font color="#804000">// SELECT automatically executes when all input variables are</font></i>
   <i><font color="#804000">// assigned. First portion of out rows is fetched to the buffer</font></i>

 <font color="#0000A0">while</font>(!i.<a href="#ref005">eof()</a>){ <i><font color="#804000">// while not end-of-data</font></i>
  i.<a href="#ref011">scanf</a>(<font color="#008080">"%d %s"</font>,&f1,f2); <i><font color="#804000">// read one row from stream</font></i>
  cout&lt;&lt;<font color="#008080">"f1="</font>&lt;&lt;f1&lt;&lt;<font color="#008080">", f2="</font>&lt;&lt;f2&lt&lt;endl;
 }
 
 i<a href="#ref003">&lt;&lt;</a>4<a href="#ref003">&lt;&lt;</a>4; <i><font color="#804000">// assigning :1 = 4, :2 = 4</font></i>
   <i><font color="#804000">// SELECT automatically re-executes when all input variables are</font></i>
   <i><font color="#804000">// assigned. First portion of out rows is fetched to the buffer</font></i>

 <font color="#0000A0">while</font>(!i.<a href="#ref005">eof()</a>){ <i><font color="#804000">// while not end-of-data</font></i>
  i.<a href="#ref011">scanf</a>(<font color="#008080">"%d %s"</font>,&f1,f2); <i><font color="#804000">// read one row from stream</font></i>
  cout&lt;&lt;<font color="#008080">"f1="</font>&lt;&lt;f1&lt;&lt;<font color="#008080">", f2="</font>&lt;&lt;f2&lt;&lt;endl;
 }

}

<h4><font color="#0000A0">int</font> main()</h4>
{
 <a href="#ref006">otl_connect::otl_initialize()</a>; <i><font color="#804000">// initialize ODBC environment</font></i>

 <font color="#0000A0">try</font>{

  db.<a href="#ref007">rlogon</a>(<font color="#008080">"UID=SCOTT;PWD=TIGER;DSN=MY_DB"</font>); <i><font color="#804000">// connect to data source MY_DB</font></i>

  <a href="#sec24">otl_cursor::direct_exec</a>
   (
    db,
    <font color="#008080">"drop table test_tab"</font>,
    <a href="#ref008">otl_exception::disabled</a> <i><font color="#804000">// disable OTL exceptions</font></i>
   ); <i><font color="#804000">// drop table</font></i>

  <a href="#sec24">otl_cursor::direct_exec</a>
   (
    db,
    <font color="#008080">"create table test_tab(f1 int, f2 varchar(30))"</font>
    );  <i><font color="#804000">// create table</font></i>

  <a href="#ref301">insert()</a>; <i><font color="#804000">// insert records into table</font></i>
  <a href="#ref302">select()</a>; <i><font color="#804000">// select records from table</font></i>

 }

 <font color="#0000A0">catch</font>(<a href="#sec23">otl_exception</a>& p){ <i><font color="#804000">// intercept OTL exceptions</font></i>
  cerr&lt;&lt;<a href="#sec23">p.msg</a>&lt;&lt;endl; <i><font color="#804000">// print out error message</font></i>
  cerr&lt;&lt;<a href="#sec23">p.code</a>&lt;&lt;endl; <i><font color="#804000">// print out error code</font></i>
  cerr&lt;&lt;<a href="#sec23">p.sqlstate</a>&lt;&lt;endl; <i><font color="#804000">// print out SQLSTATE message</font></i>
  <font color="#0000A0">if</font>(p.stm_text)
   cerr&lt;&lt;<a href="#sec23">p.stm_text</a>&lt;&lt;endl; <i><font color="#804000">// print out SQL that caused the error</font></i>
 }

 db.<a href="#ref009">logoff()</a>; <i><font color="#804000">// disconnect from the data source</font></i>

 <font color="#0000A0">return</font> 0;

}

</pre>
<h4>Output</h4>
<pre>

f1=8, f2=Name8
f1=9, f2=Name9
f1=10, f2=Name10
f1=11, f2=Name11
f1=12, f2=Name12
f1=13, f2=Name13
f1=14, f2=Name14
f1=15, f2=Name15
f1=16, f2=Name16
f1=4, f2=Name4
f1=5, f2=Name5
f1=6, f2=Name6
f1=7, f2=Name7
f1=8, f2=Name8

</pre>


<a name="sec254a"><h3>Example 4a (with otl_stream class,
TIMESTAMP_STRUCT and Oracle)</h3>
<p>
This example works with Oracle 8.x ODBC drivers only.
</p>
<h4>Source code</h4>
<pre>

<font color="#FF0000">#include &lt;iostream.h&gt;</font>
<font color="#FF0000">#include &lt;stdio.h&gt;</font>
<font color="#FF0000">#include &lt;otl.h&gt;</font>

<a href="#ref002">otl_connect</a> db; <i><font color="#804000">// connect object</font></i>

<a name="ref101a"></a><h4><font color="#0000A0">void</font> insert()</h4>
<i><font color="#804000">// insert rows into table</font></i>
{ 
 <a href="#ref001">otl_stream</a> o(3, <i><font color="#804000">// buffer size</font></i>
	      <font color="#008080">"insert into test_tab2 values(:1&lt;float&gt;,:2&lt;timestamp&gt;)"</font>, 
	         <i><font color="#804000">// SQL statement</font></i>
	      db <i><font color="#804000">// connect object</font></i>
	     );

 TIMESTAMP_STRUCT tm;

 <font color="#0000A0">for</font>(<font color="#0000A0">int</font> i=1;i&lt;=10;++i){
  tm.year=1998;
  tm.month=10;
  tm.day=19;
  tm.hour=23;
  tm.minute=12;
  tm.second=12;
  tm.fraction=0;
  o<a href="#ref003">&lt;&lt;</a>(<font color="#0000A0">float</font>)i<a href="#ref003">&lt;&lt;</a>tm;
 }
}

<a name="ref102a"></a><h4><font color="#0000A0">void</font> select()</h4>
{ 
 <a href="#ref001">otl_stream</a> i(3, <i><font color="#804000">// buffer size</font></i>
	      <font color="#008080">"select * from test_tab2 where f2=:1&lt;timestamp&gt;"</font>,
	         <i><font color="#804000">// SELECT statement</font></i>
	      db <i><font color="#804000">// connect object</font></i>
	     ); 
   <i><font color="#804000">// create select stream</font></i>
 
 <font color="#0000A0">int</font> f1;
 TIMESTAMP_STRUCT tm,f2;

 tm.year=1998;
 tm.month=10;
 tm.day=19;
 tm.hour=23;
 tm.minute=12;
 tm.second=12;
 tm.fraction=0;

 i<a href="#ref003">&lt;&lt;</a>tm; <i><font color="#804000">// assigning :1 = tm</font></i>
   <i><font color="#804000">// SELECT automatically executes when all input variables are</font></i>
   <i><font color="#804000">// assigned. First portion of out rows is fetched to the buffer</font></i>

 <font color="#0000A0">while</font>(!i.<a href="#ref005">eof()</a>){ <i><font color="#804000">// while not end-of-data</font></i>
  i<a href="#ref004">&gt;&gt;</a>f1<a href="#ref004">&gt;&gt;</a>f2;
  cout&lt;&lt;<font color="#008080">"f1="</font>&lt;&lt;f1&lt;&lt;<font color="#008080">", f2="</font>&lt;&lt;f2.month&lt;&lt;<font color="#008080">"/"</font>&lt;&lt;f2.day&lt;&lt;<font color="#008080">"/"</font>
      &lt;&lt;f2.year&lt;&lt;<font color="#008080">" "</font>&lt;&lt;f2.hour&lt;&lt;<font color="#008080">":"</font>&lt;&lt;f2.minute&lt;&lt;<font color="#008080">":"</font>
      &lt;&lt;f2.second&lt;&lt;<font color="#008080">"."</font>&lt;&lt;f2.fraction
      &lt;&lt;endl;
 }
 

}

<h4><font color="#0000A0">int</font> main()</h4>
{
 <a href="#ref006">otl_connect::otl_initialize()</a>; <i><font color="#804000">// initialize ODBC environment</font></i>
 <font color="#0000A0">try</font>{

  db.<a href="#ref007">rlogon</a>(<font color="#008080">"UID=scott;PWD=tiger;DSN=my_db"</font>); <i><font color="#804000">// connect to data source MY_DB</font></i>

  <a href="#sec24">otl_cursor::direct_exec</a>
   (
    db,
    <font color="#008080">"drop table test_tab2"</font>,
    <a href="#ref008">otl_exception::disabled</a> <i><font color="#804000">// disable OTL exceptions</font></i>
   ); <i><font color="#804000">// drop table</font></i>

  <a href="#sec24">otl_cursor::direct_exec</a>
   (
    db,
    <font color="#008080">"create table test_tab2(f1 int, f2 date)"</font>
    );  <i><font color="#804000">// create table</font></i>

  <a href="#ref101a">insert()</a>; <i><font color="#804000">// insert records into table</font></i>
  <a href="#ref102a">select()</a>; <i><font color="#804000">// select records from table</font></i>

 }

 <font color="#0000A0">catch</font>(<a href="#sec23">otl_exception</a>& p){ <i><font color="#804000">// intercept OTL exceptions</font></i>
  cerr&lt;&lt;<a href="#sec23">p.msg</a>&lt;&lt;endl; <i><font color="#804000">// print out error message</font></i>
  cerr&lt;&lt;<a href="#sec23">p.code</a>&lt;&lt;endl; <i><font color="#804000">// print out error code</font></i>
  cerr&lt;&lt;<a href="#sec23">p.sqlstate</a>&lt;&lt;endl; <i><font color="#804000">// print out SQLSTATE message</font></i>
  <font color="#0000A0">if</font>(p.stm_text)
   cerr&lt;&lt;<a href="#sec23">p.stm_text</a>&lt;&lt;endl; <i><font color="#804000">// print out SQL that caused the error</font></i>
 }

 <a href="#ref009">db.logoff()</a>; <i><font color="#804000">// disconnect from the data source</font></i>

 <font color="#0000A0">return</font> 0;

}

</pre>
<h4>Output</h4>
<pre>

f1=1, f2=10/19/1998 23:12:12.0
f1=2, f2=10/19/1998 23:12:12.0
f1=3, f2=10/19/1998 23:12:12.0
f1=4, f2=10/19/1998 23:12:12.0
f1=5, f2=10/19/1998 23:12:12.0
f1=6, f2=10/19/1998 23:12:12.0
f1=7, f2=10/19/1998 23:12:12.0
f1=8, f2=10/19/1998 23:12:12.0
f1=9, f2=10/19/1998 23:12:12.0
f1=10, f2=10/19/1998 23:12:12.0

</pre>



<a name="sec254b"><h3>Example 4b (with otl_stream class,
TIMESTAMP_STRUCT and MS SQL Server)</h3>
<p>
This example works with MS SQL Server 6.5/7.0 only.
</p>
<h4>Source code</h4>
<pre>

<font color="#FF0000">#include &lt;iostream.h&gt;</font>
<font color="#FF0000">#include &lt;stdio.h&gt;</font>
<font color="#FF0000">#include &lt;otl.h&gt;</font>

<a href="#ref002">otl_connect</a> db; <i><font color="#804000">// connect object</font></i>

<a name="ref101b"></a><h4><font color="#0000A0">void</font> insert()</h4>
<i><font color="#804000">// insert rows into table</font></i>
{ 
 <a href="#ref001">otl_stream</a> o(3, <i><font color="#804000">// buffer size</font></i>
	      <font color="#008080">"insert into test_tab2 values(:1&lt;float&gt;,:2&lt;timestamp&gt;)"</font>, 
	         <i><font color="#804000">// SQL statement</font></i>
	      db <i><font color="#804000">// connect object</font></i>
	     );

 TIMESTAMP_STRUCT tm;

 <font color="#0000A0">for</font>(<font color="#0000A0">int</font> i=1;i&lt;=10;++i){
  tm.year=1998;
  tm.month=10;
  tm.day=19;
  tm.hour=23;
  tm.minute=12;
  tm.second=12;
  tm.fraction=0;
  o<a href="#ref003">&lt;&lt;</a>(<font color="#0000A0">float</font>)i<a href="#ref003">&lt;&lt;</a>tm;
 }
}

<a name="ref102b"></a><h4><font color="#0000A0">void</font> select()</h4>
{ 
 <a href="#ref001">otl_stream</a> i(3, <i><font color="#804000">// buffer size</font></i>
	      <font color="#008080">"select * from test_tab2 where f2=:1&lt;timestamp&gt;"</font>,
	         <i><font color="#804000">// SELECT statement</font></i>
	      db <i><font color="#804000">// connect object</font></i>
	     ); 
   <i><font color="#804000">// create select stream</font></i>
 
 <font color="#0000A0">int</font> f1;
 TIMESTAMP_STRUCT tm,f2;

 tm.year=1998;
 tm.month=10;
 tm.day=19;
 tm.hour=23;
 tm.minute=12;
 tm.second=12;
 tm.fraction=0;

 i<a href="#ref003">&lt;&lt;</a>tm; <i><font color="#804000">// assigning :1 = tm</font></i>
   <i><font color="#804000">// SELECT automatically executes when all input variables are</font></i>
   <i><font color="#804000">// assigned. First portion of out rows is fetched to the buffer</font></i>

 <font color="#0000A0">while</font>(!i.<a href="#ref005">eof()</a>){ <i><font color="#804000">// while not end-of-data</font></i>
  i<a href="#ref004">&gt;&gt;</a>f1<a href="#ref004">&gt;&gt;</a>f2;
  cout&lt;&lt;<font color="#008080">"f1="</font>&lt;&lt;f1&lt;&lt;<font color="#008080">", f2="</font>&lt;&lt;f2.month&lt;&lt;<font color="#008080">"/"</font>&lt;&lt;f2.day&lt;&lt;<font color="#008080">"/"</font>
      &lt;&lt;f2.year&lt;&lt;<font color="#008080">" "</font>&lt;&lt;f2.hour&lt;&lt;<font color="#008080">":"</font>&lt;&lt;f2.minute&lt;&lt;<font color="#008080">":"</font>
      &lt;&lt;f2.second&lt;&lt;<font color="#008080">"."</font>&lt;&lt;f2.fraction
      &lt;&lt;endl;
 }
 

}

<h4><font color="#0000A0">int</font> main()</h4>
{
 <a href="#ref006">otl_connect::otl_initialize()</a>; <i><font color="#804000">// initialize ODBC environment</font></i>
 <font color="#0000A0">try</font>{

  db.<a href="#ref007">rlogon</a>(<font color="#008080">"UID=sa;PWD=;DSN=mssql"</font>); <i><font color="#804000">// connect to data source MSSQL</font></i>

  <a href="#sec24">otl_cursor::direct_exec</a>

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