# A user requests certain columns from a database

Canonical URL: <https://datadriven.io/problems/a-user-requests-certain-columns-from-a-database-use-the-b4c4a6cc>

Domain: Python · Difficulty: medium

## Problem

A user requests certain columns from a database. Use the <= operator to check if the request is a valid subset of allowed columns. Print True or False, then print the sorted list of any invalid columns (request - allowed).

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