while if loop not executing properly - php

Question

Can someone help me with the following code? The output works fine starting with the "categories" tag but the if loop only returns the last row from the db.
$strXML = "<chart> \n";
$strQuery = "select inc_type, sum(num_of_occur) as cnt from inc_detail
group by inc_type";
$query2 = mysql_query($strQuery); //call string query
$strCategories = "<categories>\n"; //create categories
while ($cat = mysql_fetch_array($query2))
{
$strCategories .= "<category label='" . $cat['inc_type'] . "' /> \n"; //display categories
};
$strCategories .= "</categories> \n";
$strQuery2 = "select agency, inc_type, sum(num_of_occur) as cnt from inc_detail group by inc_type, agency order by agency";
$query3 = mysql_query($strQuery2); //call string query
$agency = null;
while ($ds = mysql_fetch_array($query3))
{
if( $ds['agency'] != $agency )
{
$K5 = "<dataset seriesName='" . $ds['agency'] . "' /> \n"; //create dataset
$agency = $ds['agency'];
}
$K5 .= "<set value='" . $ds['cnt'] . "' /> \n"; //display value of dataset
$K5 .= "</dataset> \n";
}
$strXML .= $strCategories . $K5 . "</chart>"; //end of XML
echo $strXML;

Answer 1

The problem is here:
$K5 = "<dataset seriesName ...
You rewrite the $K5 every cycle of the iteration.
Suggested solution:
$K5 = "";
while ( ...
...
$K5 .= "<dataset seriesName ...

Answer 2

I finally got it working. For anyone interested, this is a fusionchart php file grabbing mysql data for a multiseries bar chart. Below is my new code:
$strXML = "<chart labelDisplay='Rotate' slantLabels='1' caption='Test' subCaption='By Quantity' decimalPrecision='0' showValues='0' showNames='1' numberSuffix=' Incidents' formatNumberScale='10'>";
$strQuery = "select inc_type, sum(num_of_occur) as cnt from inc_detail
group by inc_type";
$query2 = mysql_query($strQuery); //call string query
$strCategories = "<categories>"; //create categories
while ($cat = mysql_fetch_array($query2))
{
$strCategories .= "<category label='" . $cat['inc_type'] . "' />"; //display categories
}
$strCategories .= "</categories>";
$strQuery2 = "select agency, inc_type, sum(num_of_occur) as cnt from inc_detail group by inc_type, agency order by agency";
$query2 = mysql_query($strQuery2); //call string query
$K5 = $blank;
while ($ds2 = mysql_fetch_array($query2))
{
$K5 .= "<dataset seriesName='" . $ds2['agency'] . "' />"; //create dataset
//create dataset values
$strQuery4 = "select inc_type, sum(num_of_occur) as cnt from inc_detail where agency = '$ds2[agency]' group by inc_type";
$query4 = mysql_query($strQuery4);
while ($ds4 = mysql_fetch_array($query4))
{
$K5 .= "<set value='" . $ds4['cnt'] . "' />"; //display value of dataset
}
$K5 .= "</dataset>";
}
$strXML .= $strCategories . $K5 . "</chart>"; //end of XML
echo renderChart("fc/MSColumn3D.swf", "", $strXML, "productSales", 900, 600);