How can I check if an item is stored in a shelve database quickly?

Question

I'm working with the shelve library, on Python 3.8.3., and I'm fairly confident with creating new entries from a database, and reading a certain key's values. However, I can't do something like this:

users = shelve.open("users", "r")
name = input()
if name in users:
    do something
else:
    do something else
users.close()

Since I don't have access to the dictionary directly, but to a shelve object. I suppose I could turn the keys into a list, but that would defeat the whole purpose of using a dictionary. Any ideias?

@VictorS, the name is supposed to be a user's username, and the shelve's keys are the names. So, for example, if you had already registered under "Victor", users["Victor"] would have some information about your account. — J. Dionisio, Jul 04 '20 at 13:30
@VictorS, users is a shelve object. But, as a dictionary, it should look like {n1: ['asd', 0, 0], n2:['fs',12,421]...} — J. Dionisio, Jul 04 '20 at 13:50

score 0 · Accepted Answer · answered Jul 07 '20 at 14:39

It appears that I am very dumb. I was reading from a file called "users" and writing to a file called "users.txt", and that's what was where the mistake was coming from. You can do what I said in the original post, if name in users....

The error message was not very indicative of this error though (of a key error), so I'll leave the question up for posterity.

How can I check if an item is stored in a shelve database quickly?

1 Answers1