通過時移獲取數據-PHP MYSQL

Question

我正在基於輪班的應用程序上工作，我的工作人員分三班倒，早上6點至下午2點，下午2點至10點，晚上10點至6點（第二天）。 我需要計算記錄在數據庫中的每個班次的總工作時間。

  $clientid = $_GET["clientid"];
  $date = $_GET["edate"];
  $shift = $_GET["shift"];

  if(!empty($clientid))
  {
    if($shift=='a')
    {
      $sq =  mysql_query("SELECT * from logusage WHERE etime BETWEEN '6:00:00' AND '14:00:00' AND clientid= '$clientid' AND edate = '$date'",$this->db);
    }
    else if($shift=='b')
    {
      $sq =  mysql_query("SELECT * from logusage WHERE etime BETWEEN '14:00:00' AND '22:00:00' AND clientid= '$clientid' AND edate = '$date'",$this->db);
    }
    else if($shift=='c')
    {
      $sq =  mysql_query("SELECT * from logusage WHERE etime BETWEEN '22:00:00' AND '6:00:00' AND clientid= '$clientid' AND edate= '$date'",$this->db);
    }

每當我嘗試訪問Shift C時，由於我也正在解析日期，因此它僅在當天的11點59分之前獲取我的數據。 我如何更改sql以第二天獲取數據，直到凌晨6點？

Answer 1

對於第三個，您需要減去幾個小時才能使日期正確：

SELECT * 
FROM logusage
WHERE etime BETWEEN '22:00:00' AND '6:00:00' AND
      clientid= '$clientid' AND
      date(date_sub(edate, interval 6 hour)) = '$date';

Answer 2

我強烈建議您將EDATE和ETIME作為TIMESTAMP值而不是2個單獨的列存儲在單個列中。 將時間戳記存儲為GMT + 00值而不是本地時間也是一種好習慣-但這僅在本地時間使用DST（夏令時）時才重要。 嘗試以下代碼：

$clientid = (int)$_GET["clientid"];
$date = $_GET["edate"];
$shift = $_GET["shift"];

if($clientid != 0 AND $date != '')
{
    // I suppose $date is in format YYYY-MM-DD
    list($year,$month,$day) = preg_split('/-/',$date);
    switch($shift)
    {
        case 'a':
            $beg_stamp = mktime(6,0,0,$month,$day,$year);
            $end_stamp = $beg_stamp + 8*3600 - 1;
            break;
        case 'b':
            $beg_stamp = mktime(14,0,0,$month,$day,$year);
            $end_stamp = $beg_stamp + 8*3600 - 1;
            break;
        case 'c':
            $beg_stamp = mktime(22,0,0,$month,$day,$year);
            $end_stamp = $beg_stamp + 8*3600 - 1;
            break;
    }
    if($beg_stamp != '' AND $end_stamp != '') // not strictly needed, if $shift is always valid
        $sq = mysql_query('SELECT * from logusage WHERE clientid = '.$clientid.' AND TIMESTAMP(edate,etime) BETWEEN "'.date('Y-m-d H:i:s',$beg_stamp).'" AND "'.date('Y-m-d H:i:s',$end_stamp).'" ORDER BY edate,etime',$this->db);
}

您從$ end_stamp中減去1，因為SQL謂詞BETWEEN是包含在內的-即x BETWEEN y AND z等於x> = y AND x <= z，並且您不想捕獲屬於下一個班次的工作。