嵌套的foreach循环给出了奇怪的增量结果

Question

I am planning on building an html table filled with locations followed by 2 subcategories of things, all pulled from the database and stored in a PHP array. Something weird is going on with my foreach loop.

    $loc_query = "SELECT Location FROM Locations;";
    $loc_result = $mysqli->query($loc_query);

    while($row = $loc_result->fetch_assoc()){
    $loc_results[] = $row;
    }


    foreach($loc_results as $loc){
        echo '<tr align="right"><td width="20" align="center" onmousedown="show()" bordercolor="#000000"
         style="cursor:pointer;font-size:10pt;font-weight:bold;border-style:solid;border-width:1pt">+</td>
         <td width="120" align="left" 
         bgcolor="#00FFFF" style="border-top-style:solid;border-top-width:1pt;border-right-style:solid;
         border-right-width:1pt;border-bottom-style:solid;border-bottom-width:1pt" >'.$loc['Location'].'</td></tr>';

        $CC_query = "SELECT Cost_Center_Category.Cost_Center_Category_Name, Cost_Center_Name, 
        Locations.Location_Abbrev, Locations.Location, LC, 
        FX, RR_In_LC, Hours 
        FROM Cost_Centers 
        LEFT JOIN Cost_Center_Category 
        ON Cost_Centers.Cost_Center_Category = Cost_Center_Category.Cost_Center_Category_ID 
        LEFT JOIN Locations ON Cost_Centers.Location = Locations.Location_Abbrev;";

        $CC_result = $mysqli->query($CC_query);


        while($row = $CC_result->fetch_assoc()){
            $CC_results[] = $row;
        }

        foreach ($CC_results as $result){
            switch($result['Cost_Center_Category_Name'])
            {
                case 'Strategy & Performance' :
                    echo '<tr align="right"><td width="20" align="center" onmousedown="show()" bordercolor="#000000"
                     style="cursor:pointer;font-size:10pt;font-weight:bold;border-style:solid;border-width:1pt">+</td>
                     <td width="150" align="left"
                      bgcolor="#FFCC00" 
                      style="border-top-style:solid;border-top-width:1pt;border-right-style:solid;
                      border-right-width:1pt;border-bottom-style:
                      solid;border-bottom-width:1pt"
                       onmousedown="show()">'.$result['Cost_Center_Category_Name'].'</td></tr>';

                    break;

            }
        }
    }

It outputs all the locations fine, but once I try to populate each location with a cost center category, it outputs something like

• Nuremberg
• Strategy & Performance
• Regensburg
• Strategy & Performance
• Strategy & Performance
• Sibiu
• Strategy & Performance
• Strategy & Performance
• Strategy & Performance

and it grows each time. I know it must be something to do with my logic, I've tried things like break 2 and I think I've been staring at it too long, it's probably really obvious. Is there something wrong with the way I set up the nested loops or is it something else?

Answer 1

Reset $CC_results to empty array on every iteration of foreach loop:

foreach($loc_results as $loc) {
    $CC_results = array();

    // all other code stays the same

}