Question

我的num_rows回來爲0，我試着用幾種方式調用它，但我卡住了。這裏是我的代碼：

$conn = new mysqli($dbserver, "dbuser", "dbpass", $dbname); 

    // get the data 
    $sql = 'SELECT AT.activityName, AT.createdOn 
      FROM userActivity UA, users U, activityType AT 
      WHERE U.userId = UA.userId 
      and AT.activityType = UA.activityType 
      and U.username = ? 
      order by AT.createdOn';    
    $stmt = $conn->stmt_init(); 
    $stmt->prepare($sql); 
    $stmt->bind_param('s', $requestedUsername); 
    $stmt->bind_result($activityName, $createdOn); 
    $stmt->execute(); 

    // display the data 
    $numrows = $stmt->num_rows; 
    $result=array("user activity report for: " . $requestedUsername . " with " . $numrows . " rows:"); 
    $result[]="Created On --- Activity Name"; 
    while ($stmt->fetch()) 
    { 
     $msg = " " . $createdOn . " --- " . $activityName . " "; 
     $result[] = $msg; 
    } 

    $stmt->close(); 

找到了多行，並且抓取循環處理它們就好了。有什麼建議可以讓我獲得查詢中返回的行數？

建議非常感謝。提前致謝。

Answer 1

你需要調用$stmt->store_result()第一，只是$stmt->num_rows之前。

Answer 2

嘗試在調用num_rows;之前添加它。

$stmt->store_result();

Answer 3

我不知道這是否會修復它，但你不能bind_results直到後你execute查詢，如果我沒有弄錯。

而且while循環：

while ($stmt->fetch()) 
{ 
    $msg = " " . $createdOn . " --- " . $activityName . " "; 
    $result[] = $msg; 
} 

你將失去​​所有的$msg變量與循環的每次迭代中，除了最後一個設置，因爲你要麼需要做$msg .=或使$msg數組$msg[] =

Answer 4

$stmt->store_result(); 
$numrows = $stmt->num_rows; 

檢查：http://php.net/manual/en/mysqli-result.num-rows.php，這 http://php.net/manual/en/mysqli-stmt.num-rows.php