Python sqlite3 select where not row equals each element of list

Question

I have a list in python:

usernames = ["username 1", "Username 2", ... "Username 3"]

I have to perform a sql query to select all rows from a table where not username equals any of the elements in the list.

results = cursor.execute("SELECT * FROM table WHERE NOT username = ?", usernames)

How can I achieve this?

Answer 1

You could use NOT IN condition. Unfortunately, you cannot replace a placeholder with a list of values, so, you have to create a placeholder for each element in the usernames list:

In [24]: c.execute('SELECT * FROM test').fetchall()
Out[24]: [('name1',), ('name2',), ('name3',)]

In [25]: usernames = ['name2', 'name4', 'name5']

In [26]: sql = 'SELECT * FROM test WHERE name NOT IN ({})'.format(','.join('?' * len(usernames)))

In [27]: c.execute(sql, usernames).fetchall()
Out[27]: [('name1',), ('name3',)]

In [28]: usernames += ['name1']

In [29]: sql = 'SELECT * FROM test WHERE name NOT IN ({})'.format(','.join('?' * len(usernames)))

In [30]: c.execute(sql, usernames).fetchall()
Out[30]: [('name3',)]