而if循环没有正确执行

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> 
";


$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";
$query3 = mysql_query($strQuery2); //call string query
$agency = null;
while ($ds = mysql_fetch_array($query3))
{
    if( $ds['agency'] != $agency )
  {
    $K5 = "<dataset seriesName='" . $ds['agency'] . "' /> 
"; //create dataset
    $agency = $ds['agency'];
  }
    $K5 .= "<set value='" . $ds['cnt'] . "' /> 
"; //display value of dataset
    $K5 .= "</dataset> 
";
}


$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 ...