I’m having trouble printing database values

Question

I am trying to print the 'ok' on the screen when it finds the value '3' inside one of the Keys of the database.

>>> with dbm.open('data1.db','r') as user:
    user['0'] = '1'
    user['1'] = '2'
    user['2'] = '3'
    for i in user:
        if '3' in user[str(i)]:
            print('ok')


Traceback (most recent call last):
  File "<pyshell#146>", line 3, in <module>
    if '3' in user[str(i)]:
  File "C:\Users\ThomasNote\AppData\Local\Programs\Python\Python36-32\lib\dbm\dumb.py", line 148, in __getitem__
    pos, siz = self._index[key]     # may raise KeyError
KeyError: b"b'0'"




with dbm.open('data1.db','r') as user:
    for i in user:
        print(i.decode(), user[i].decode())

>>> 0 1
>>> 1 2
>>> 2 3 

Answer 1

By the type of error it seems that the user list you are trying to update is not initialized in the corresponding keys.

However, starting from the premise that the user list has been initialized and updated correctly, try the following loop.

    for i in user:
     if (i=='3'):
      print('ok')