“多个SELECT，INNER JOIN”sql查询无法正常工作

Question

I tested my sql query in phpMyAdmin and it works there. But when I copy it and paste in my code then it return NULL. My other code is error-free as it works perfect when I remove this sql query. Thus, I believe there is some problem with this query. I spent 2 days to find the problem. One important thing is that it works if I remove INNER JOIN . I tried using JOIN and FULL JOIN, but none of them works. Does anyone see any problem with this query?

Below is my query :

SELECT *
    From (
      SELECT userTrip.id,userTrip.fromLat,userTrip.fromLon,userTrip.toLat,userTrip.toLon
          From userTrip
              WHERE userTrip.userId != :userId
              AND userTrip.departureTime > CURDATE()
              AND ABS(UNIX_TIMESTAMP(userTrip.departureTime) - UNIX_TIMESTAMP(:departureTime)) <= " . DEPARTURETIME_DIFFERENCE_THRESHOLD . " * 60
              AND userTrip.fromLat Between :fromMinLat AND :fromMaxLat
              AND userTrip.fromLon Between :fromMinLon AND :fromMaxLon
          ) AS SourcesNearBy FULL JOIN user ON user.id = SourcesNearBy.userId ORDER BY user.id
        WHERE toLat Between :toMinLat AND :toMaxLat
        AND toLon Between :toMinLon AND :toMaxLon
        AND (user.gender LIKE :matchGender OR :matchGender LIKE 'A')
        AND (:matchAge = -1 OR (CAST(DATEDIFF(CURDATE(),user.birthdate)/365.25 AS UNSIGNED) Between (:matchAge - " . MAX_AGE_DIFFERENCE . ") AND (:matchAge + " . MAX_AGE_DIFFERENCE . ")))

Thank you.

This is my code :

public function findMatchesForUser($userId,$tripId)
    {
        $sql = "SELECT * from userTrip WHERE tripFinished = 0 AND id = :tripId";
        $stmt = $this->dbLink->prepare($sql);
        $stmt->bindParam(':tripId', $tripId, PDO::PARAM_INT);

        try
        {
            $stmt->execute();
            $userTrip = $stmt->fetchObject();
        }
        catch (PDOException $err)
        {
            echo $err->getMessage();
        }

        if ($userTrip == null)
            throw new Frapi_Error('Error Code : 500. Try again.');

        // get user's trip length
        $distanceClass = new Distance();
        $userTripLength = $distanceClass->drivingDistance($userTrip->fromLat, $userTrip->fromLon, $userTrip->toLat, $userTrip->toLon);

        // set up first bounding square
        $this->setUpBoundingSquare($userTrip->fromLat, $userTrip->fromLon, $userTripLength * SOURCE_DISTANCE_THRESHOLD / 100, 1);
        // set up bounding second square
        $this->setUpBoundingSquare($userTrip->toLat, $userTrip->toLon, $userTripLength * DESTINATION_DISTANCE_THRESHOLD / 100, 0);

        // perform first phase of algorithm
        $Candidates = $this->firstPhase($userId,$userTrip);
    }


private function firstPhase($userId,$userTrip)
    {
        $sql = "SELECT *
                  From (
                          SELECT userTrip.id,userTrip.fromLat,userTrip.fromLon,userTrip.toLat,userTrip.toLon
                              From userTrip INNER JOIN user ON userTrip.userId = user.id
                                  WHERE userTrip.userId != :userId
                                  AND (user.gender LIKE :matchGender OR :matchGender LIKE 'A')
                                  AND (:matchAge = -1 OR (CAST(DATEDIFF(CURDATE(),user.birthdate)/365.25 AS UNSIGNED) Between (:matchAge - " . MAX_AGE_DIFFERENCE . ") AND (:matchAge + " . MAX_AGE_DIFFERENCE . ")))
                                  AND userTrip.departureTime > '".date('Y-m-d H:i:s')."'
                                  AND ABS(UNIX_TIMESTAMP(userTrip.departureTime) - UNIX_TIMESTAMP(:departureTime)) <= " . DEPARTURETIME_DIFFERENCE_THRESHOLD . " * 60
                                  AND userTrip.fromLat Between :fromMinLat AND :fromMaxLat
                                  AND userTrip.fromLon Between :fromMinLon AND :fromMaxLon
                      ) AS SourcesNearBy
                      WHERE toLat Between :toMinLat AND :toMaxLat
                      AND toLon Between :toMinLon AND :toMaxLon;";

        $stmt = $this->dbLink->prepare($sql);

        // Bind parameters

        $stmt->bindParam(':fromMinLat', $this->fromMinLat, PDO::PARAM_STR);
        $stmt->bindParam(':fromMinLon', $this->fromMinLon, PDO::PARAM_STR);
        $stmt->bindParam(':fromMaxLat', $this->fromMaxLat, PDO::PARAM_STR);
        $stmt->bindParam(':fromMaxLon', $this->fromMaxLon, PDO::PARAM_STR);
        $stmt->bindParam(':toMinLat', $this->toMinLat, PDO::PARAM_STR);
        $stmt->bindParam(':toMinLon', $this->toMinLon, PDO::PARAM_STR);
        $stmt->bindParam(':toMaxLat', $this->toMaxLat, PDO::PARAM_STR);
        $stmt->bindParam(':toMaxLon', $this->toMaxLon, PDO::PARAM_STR);
        $stmt->bindParam(':userId', $userId, PDO::PARAM_INT);
        $stmt->bindParam(':matchGender', $userTrip->matchGender, PDO::PARAM_STR);
        $stmt->bindParam(':matchAge', $userTrip->matchAge, PDO::PARAM_INT);
        $stmt->bindParam(':departureTime', $userTrip->departureTime, PDO::PARAM_STR);

        try
        {
            $stmt->execute();
            $Candidates = $stmt->fetchAll();
        }
        catch (PDOException $err)
        {
            echo $err->getMessage();
        }
        // If no matchCandidates
        if ($Candidates == null)
            throw new Frapi_Error("No match candidates found!");

        return $Candidates;
    }

The alternate query which runs perfect. But it is not good at performance. I want to shift INNER JOIN in outer SELECT.

$sql = "SELECT *
                  From (
                        SELECT userTrip.id,userTrip.fromLat,userTrip.fromLon,userTrip.toLat,userTrip.toLon
                            From userTrip INNER JOIN user ON userTrip.userId = user.id
                                WHERE userTrip.userId != :userId
                                  AND (user.gender LIKE :matchGender OR :matchGender LIKE 'A')
                                  AND (:matchAge = -1 OR (CAST(DATEDIFF(CURDATE(),user.birthdate)/365.25 AS UNSIGNED) Between (:matchAge - " . MAX_AGE_DIFFERENCE . ") AND (:matchAge + " . MAX_AGE_DIFFERENCE . ")))
                                  AND userTrip.departureTime > '".date('Y-m-d H:i:s')."'
                                  AND ABS(UNIX_TIMESTAMP(userTrip.departureTime) - UNIX_TIMESTAMP(:departureTime)) <= " . DEPARTURETIME_DIFFERENCE_THRESHOLD . " * 60
                                  AND userTrip.fromLat Between :fromMinLat AND :fromMaxLat
                                  AND userTrip.fromLon Between :fromMinLon AND :fromMaxLon
                      ) AS SourcesNearBy
                      WHERE toLat Between :toMinLat AND :toMaxLat
                      AND toLon Between :toMinLon AND :toMaxLon;";

Query by removing FULL JOIN

SELECT *
    From (
      SELECT userTrip.id,userTrip.fromLat,userTrip.fromLon,userTrip.toLat,userTrip.toLon
          From userTrip
              WHERE userTrip.userId != :userId
              AND userTrip.departureTime > CURDATE()
              AND ABS(UNIX_TIMESTAMP(userTrip.departureTime) - UNIX_TIMESTAMP(:departureTime)) <= " . DEPARTURETIME_DIFFERENCE_THRESHOLD . " * 60
              AND userTrip.fromLat Between :fromMinLat AND :fromMaxLat
              AND userTrip.fromLon Between :fromMinLon AND :fromMaxLon
          ) AS SourcesNearBy INNER JOIN user ON user.id = SourcesNearBy.userId
        WHERE toLat Between :toMinLat AND :toMaxLat
        AND toLon Between :toMinLon AND :toMaxLon
        AND (user.gender LIKE :matchGender OR :matchGender LIKE 'A')
        AND (:matchAge = -1 OR (CAST(DATEDIFF(CURDATE(),user.birthdate)/365.25 AS UNSIGNED) Between (:matchAge - " . MAX_AGE_DIFFERENCE . ") AND (:matchAge + " . MAX_AGE_DIFFERENCE . ")))

userTrip Table

id | userName<br>

 1 |     A<br>
 2 |     B<br>
 3 |     C<br>
 4 |     D<br>
 5 |     E<br>
 6 |     F<br>

user Table

id | userId | fromLat | fromLon | toLat | toLon | departureTime | matchGender | matchAge<br>
  5 | 1 | 40.712898 | -74.013199 | 40.728157 | -74.077644 | 2013-04-26 15:56:08 | M | 25<br>
 10 | 2 | 28.520140 | -81.388771 | 28.054642 | -82.469940 | 2013-01-17 10:34:56 | F | 30<br>

Answer 1

You appear to have a random ORDER BY user.id in the middle of your SELECT statement.

EDIT - Playing around with your code, there is no need for a subselect anyway.

Something like this should do it.:-

SELECT userTrip.id,userTrip.fromLat,userTrip.fromLon,userTrip.toLat,userTrip.toLon
FROM userTrip 
INNER JOIN user 
ON userTrip.userId = user.id
WHERE userTrip.userId != :userId
AND (user.gender LIKE :matchGender OR :matchGender LIKE 'A')
AND (:matchAge = -1 OR (CAST(DATEDIFF(CURDATE(),user.birthdate)/365.25 AS UNSIGNED) BETWEEN (:matchAge - " . MAX_AGE_DIFFERENCE . ") AND (:matchAge + " . MAX_AGE_DIFFERENCE . ")))
AND userTrip.departureTime > '".date('Y-m-d H:i:s')."'
AND ABS(UNIX_TIMESTAMP(userTrip.departureTime) - UNIX_TIMESTAMP(:departureTime)) <= " . DEPARTURETIME_DIFFERENCE_THRESHOLD . " * 60
AND userTrip.fromLat BETWEEN :fromMinLat AND :fromMaxLat
AND userTrip.fromLon BETWEEN :fromMinLon AND :fromMaxLon
AND toLat BETWEEN :toMinLat AND :toMaxLat
AND toLon BETWEEN :toMinLon AND :toMaxLon

Try that with some real values. If it performs poorly then I suspect the issue is down to indexes, so do an EXPLAIN and post the results.

Answer 2

您是否使用变量值运行查询，即查询中可能存在某些可能包含错误值的变量。请查询查询绝对正常。