MYSQL雖然與mysql_fetch_assoc不返回時= 1

Question

我有以下的PHP，從MySQL查詢創建一些JSON。當有多個元素，即mysql_fetch_assoc> 1，但是如果它= 1，那麼沒有任何工作和調試，while循環內的任何echo語句都不會被調用！

這是怎麼回事？

$byFlight = mysql_query($query_byFlight, $pfArchiveDB) or die(mysql_error()); 
$row_byFlight = mysql_fetch_assoc($byFlight); 
//$totalRows_byFlight = mysql_num_rows($byFlight); 
//echo ($query_byFlight); 
$flights = array(); 
if(mysql_num_rows($byFlight)) { 
    while($flight = mysql_fetch_assoc($byFlight)) { 
     $flights[] = array('flight'=>$flight); 
    } 
} 
header('Content-type: application/json'); 
echo json_encode(array('flights'=>$flights)); 

Answer 1

您正在執行兩次提取操作，並且這可能會消耗您的第一行。 此代碼將正常工作：

$byFlight = mysql_query($query_byFlight, $pfArchiveDB) or die(mysql_error()); 

//$row_byFlight = mysql_fetch_assoc($byFlight); // <---- COMMENTED THIS FETCH 

//$totalRows_byFlight = mysql_num_rows($byFlight); 
//echo ($query_byFlight); 
$flights = array(); 
if(mysql_num_rows($byFlight)) { 
    while($flight = mysql_fetch_assoc($byFlight)) { 
     $flights[] = array('flight'=>$flight); 
    } 
} 
header('Content-type: application/json'); 
echo json_encode(array('flights'=>$flights));