Working with arrays

[zyberpunker]

Is it possible to work with arrays in tinydb?
For example, how can I update an array with cars if I would like to add 'bmw' to the following?
{'name': 'Bob', 'cars': ['volvo', 'mazda']}

[msiemens]

Hey @zyberpunker,

you use db.update and pass an update function as the second parameter (see https://tinydb.readthedocs.io/en/latest/usage.html#updating-data although it doesn't make this pattern clear):

db.update(where('name') == 'Bob, lambda doc: doc['contents'].append('bmw'))

The lambda here gets the matching document and can modify it however it likes. You can append data, remove it etc.

Can you verify this works for you?

[MrLucio]

Hi,

thank you for the reply, I too was looking for a push-like method.
I can confirm it works with a minor change to db.update, regarding the order or the parameters:

db.update(lambda doc: doc['cars'].append('bmw'), where('name') == 'Bob')

The order of parameters you used will cause the updates issued by the lamda to be applied to all documents with no filtering whatsoever.

[msiemens]

Oh, you're right, I confused the order of the arguments! It's the operation first, then the search condition 🙂