logginghandleruse.htm

The goal of this library is to make ODBC recordsets look just like an STL container. As a user, you

<pre><code><span class="codeComment">// Example Code Using LoggingHandler on a DBView

// test of failed SelValidate() when reading data</span>
void TestBadSelValidate()
{
 	vector&lt;Example&gt; results;

	<span class="codeComment">// construct view
	// DBView&lt;Example&gt; is actually DBView&lt;Example, 
	// DefaultParamObj&lt;Example&gt; &gt; thanks to the default 
	// argument to the DBView template

	// use our bad BCA which references a nonexistent column name in DB_EXAMPLE</span>
	DBView&lt;Example&gt;
		view(&quot;DB_EXAMPLE&quot;, BCAExampleObj(),
		&quot;WHERE INT_VALUE BETWEEN (?) AND (?) AND &quot;
		&quot;STRING_VALUE = (?) OR EXAMPLE_DATE &lt; (?) ORDER BY EXAMPLE_LONG&quot;,
		BPAExampleObj(), BadSelValidate());

	<span class="codeComment">// loop through query results and add them to our vector
	// in this loop, read_it.GetLastCount() records read from DB</span>

	DBView&lt;Example&gt;::select_iterator read_it = view.begin();

	<span class="codeComment">// set parameter values for the WHERE clause in our SQL query</span>
	read_it.Params().lowIntValue = 2;
	read_it.Params().highIntValue = 8;
	read_it.Params().strValue = &quot;Example&quot;;
	
	TIMESTAMP_STRUCT paramDate = {2000, 1, 1, 0, 0, 0, 0};
	read_it.Params().dateValue = paramDate;

	for ( ; read_it != view.end(); read_it++)
	{
	try
		{
		  <span class="codeComment">// note that the read_iterator::GetLastCount()  is incremented in operator++()
		  // remember that the record is fetched and thus the count incremented
		  // before operator*() is applied to the read_iterator</span>

		  cout &lt;&lt; &quot;Reading element #&quot; &lt;&lt; read_it.GetLastCount() &lt;&lt; endl;
		  
		  cout &lt;&lt; &quot;read_it-&gt;exampleInt = &quot; &lt;&lt; read_it-&gt;exampleInt &lt;&lt; endl;
		  cout &lt;&lt; &quot;read_it-&gt;exampleStr = &quot; &lt;&lt; read_it-&gt;exampleStr &lt;&lt; endl;
		  
		  results.push_back(*read_it);
		}
		catch (RootException &amp;ex)
		{
		  cout &lt;&lt; &quot;Caught Exception!!!!&quot; &lt;&lt; endl;
		  cout &lt;&lt; ex.what() &lt;&lt; endl;
		}
	}

	LoggingHandler&lt;Example&gt; handler = 
		read_it.get_io_handler((LoggingHandler&lt;Example&gt; *) NULL);

	typedef LoggingHandler&lt;Example&gt;::LoggedTriple LoggedTriple;

	vector&lt;LoggedTriple&gt; errors = handler.GetLog();

	for (vector&lt;LoggedTriple&gt;::iterator log_it = errors.begin(); log_it != errors.end();
			log_it++)
	{
		LoggedTriple error = *log_it;

		cout &lt;&lt; &quot;Error msg = &quot; &lt;&lt; error.errmsg &lt;&lt; endl;
		cout &lt;&lt; &quot;Example = &quot; &lt;&lt; error.dataObj &lt;&lt; endl;
	}

}
</code></pre>