“多个SELECT，INNER JOIN”sql查询无法正常工作

时间：2013-04-17 10:45:35

标签： mysql sql join inner-join multiple-select-query

我在phpMyAdmin中测试了我的sql查询，它在那里工作。但是当我复制它并粘贴到我的代码中时它返回NULL。我的其他代码没有错误，因为当我删除这个SQL查询时，它完美无缺。因此，我相信这个查询存在一些问题。我花了2天时间才发现问题。一件重要的事情是it works if I remove INNER JOIN。我尝试使用JOIN和FULL JOIN，但它们都不起作用。有没有人发现此查询有任何问题？

以下是我的询问：

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 . ")))

谢谢。

这是我的代码：

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;
    }

运行完美的备用查询。但它在表现上并不擅长。我想在外部SELECT中移动INNER JOIN。

$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;";

通过删除FULL JOIN进行查询 

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表 

id | userName<br>

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

用户表 

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>

2 个答案:

答案 0 :(得分：2)

您的SELECT语句中间似乎有一个随机 ORDER BY user.id 。

编辑 - 使用您的代码，无论如何都不需要子选择。

这样的事情应该这样做。： - 

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

尝试一些真实的价值观。如果它表现不佳，那么我怀疑问题归结为索引，因此请使用EXPLAIN并发布结果。

答案 1 :(得分：0)

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。请查看查询绝对正常。

相关问题
最新问题