SQL query won't populate my drop-down box

I have a problem with this query and drop down box:

$ziua = "SELECT DISTINCT DA开发者_运维问答YOFMONTH(ziua) FROM rapoarte"; 

$ziuaResult = mysql_query($ziua);

Populating the drop down box :

echo"<td>Selectati Ziua:</td>    
<td><select name='ziua'>     
<option value='---'>---</option>";

while($ziuaRow = mysql_fetch_array($ziuaResult)) 
{    
    $ziua1 = $ziuaRow['ziua'];     
    echo "<option value='$ziua1'>$ziua1</option>";
}

For an reason unknown to me, the drop down box is populated, but no values are shown. (there are 2-3 empty options)

That happens because there is no such column ziua in your query. Use alias in the query SELECT DISTINCT DAYOFMONTH(ziua) as dm FROM rapoarte and then $ziua1 = $ziuaRow['dm']; or access result by integer index $ziua1 = $ziuaRow[0];

The problem is that the field name is not correct. I have tried that as well. It will give you the reult.