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SQLite3 select previous row to do some math

Hi,

I'm trying to find out how I can select data from the previous row.
I'm storing GPS data into my database. When I'm reading the data into the database I want to select the previous row and then use this data to calculate the distance between previous point and real point.
for the calculation I will use the Haversin Algoritme.

So this is what I tryed to select the previous row.

                                print (gpsTime)
                                print (gpsLat)
                                print (gpsLon)
                                print (drivingTime)
                               drivenTime = int(drivingTime)-1
                                print (drivenTime)

                                if drivingTime > 0:
                                        previousLon = c.execute('SELECT longitude FROM readings where id=?')
                                        result = cursor.execute(previousLon, (drivenTime,))
                                        print (result)

So the result of this is the following: I get the first 2 datapoints but after  the following error.

2016-08-20T06:53:56.000Z
50.991696667
4.282545
0
-1
2016-08-20T06:53:57.000Z
50.991696667
4.282545
1
0
Traceback (most recent call last):
  File "GPSCoordinatesToMeters.py", line 60, in <module>
    previousLon = c.execute('SELECT longitude FROM readings where id=?')
sqlite3.ProgrammingError: Incorrect number of bindings supplied. The current statement uses 1, and there are 0 supplied.


Any Idea what the problem is here?

Kind regards Toon