Question

要生成报告，我需要编写连接查询。我现在在sql中编写了连接查询，我需要在laravel 5.2中编写相同的查询。我的SQL查询如下所示。

SELECT a.accountID, a.deviceID, b.description, a.timestamp, a.latitude, a.longitude, a.speedKPH as speed, a.heading, a.altitude, a.address, a.distanceKM as distance, a.odometerKM as odometer, a.IbatVolts, a.EbatVolts, a.ITempr, a.fuelLevel, a.inputState, a.IgnRuntime, a.GPSFixType, a.GPSPDOP, a.AlertType, a.speedLimitKPH, a.isTollRoad
FROM eventdata as a, device as b 
WHERE a.deviceID = '$deviceID'
  AND a.accountID = '$accountID'
  AND a.timestamp >= $dt1
  AND a.timestamp <= $dt2
  AND a.deviceID=b.deviceID
ORDER BY timestamp DESC

我也尝试用laravel写它。查询如下：

DB::table('device as b')
   ->join('eventdata as a', 'a.deviceID', '=', 'b.deviceID')
   ->where('a.deviceID', '=', '$deviceID')
   ->where('a.accountID', '=', '$accountID')
   ->where('a.timestamp', '>=', '$dt1')
   ->where('a.timestamp', '<=', '$dt2')
   ->select('a.accountID', 'a.deviceID', 'b.description', 'a.timestamp',
            'a.latitude', 'a.longitude', 'a.speed', 'a.heading', 'a.altitude', 'a.address', 'a.distanceKM as distance', 'a.odometerKM as odometer', 'a.IbatVolts', 'a.EbatVolts', 'a.ITempr', 'a.fuelLevel', 'a.inputState', 'a.IgnRuntime', 'GPSFixType', 'a.GPSPDOP', 'a.AlterType', 'a.speedLimitKPH', 'a.isTollRoad')->get():

这是对的吗？谁能告诉我并帮我写出正确的查询。

Answer 1

laravel 5.2中的连接语法是：

$users = DB::table('users')
            ->join('contacts', 'users.id', '=', 'contacts.user_id')
            ->join('orders', 'users.id', '=', 'orders.user_id')
            ->select('users.*', 'contacts.phone', 'orders.price')
            ->get();

你正在使用相同的。如果您遇到任何问题，可以使用以下方法打印原始sql查询：

DB::enableQueryLog();

// Your query

$queries = DB::getQueryLog();
print_r($queries);  // it will print raw sql query in prepared statement style

如何在laravel 5.2中编写sql join查询

1 个答案: