SQLite without a model class

So we are working on an app where we handle a big amount of data, we receive all of it one-shot in multiple .txt tables and the data doesn't change for a week. The user then will interact with this data (in read-only) through the different pages of the app.

Since i don't want to saturate the RAM with all this data (it's causing memory crashs), i would like to convert it all after receiving it into an SQLite DB and then read from that when needed.

My problem is simple, the data is completely variable and i don't have fixed columns for me to create an object model, the columns are only fixed for that one week since the tables don't change.

Looking through the examples of SQLite implementation it is all done with a model class that defines the different columns of the DB.

Is it possible to get around this? how? i just want a 'smart' dictionary that resides in storage and not in RAM from which i can read my data by querying with the id+column_name, is SQLite even the best solution for this?

Thank you very much for your help kind devs :)