Python- How to see if a db key exists?

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Python- How to see if a db key exists?

I want to make something so that if I want to add something to a key that doesn't exist, it will create the key, then add it. But I can't find a way to test whether it already exists or not.

Answered by IMayBeMe (346) [earned 5 cycles]

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You can probably try to add it by using try and if it returns an error then use except to create the key and add the value. For example:

def add_to_db():
  try:
    #add a value to the key
  except:
    #Create a key and adds the value

the db can be treated like a dict. You can check if a dict contains a key like this:

if key in db:

where key is the key.

A more idiomatic approach is:

try:
  db[key]
except:
  # key doesn't exist, do something

where key, of course, is the key.

db['hello'] = 'yes'

if 'hello' in db: # checks if the key 'hello' is in the dict
  # something

else: # if not, adds it.
  db['hello'] = 'something'

Try something like this

from replit import db
#create a list of keys
keys=list(db.keys())
#set key to "a key"
key="a key"
#if the key is already in the list
if key in keys:
  print("That already exists")
#if the key isn't in the list
elif key not in keys:
#set value at the key to whatever you want
  db[key]="whatever you want"