unit testing for sql queries

I have a function that looks like this:

  def finding_info(self):
    query = """
    SELECT u.name, u.id, 
       t.number_of_tasks,
    FROM users u
    INNER JOIN (
      SELECT userId, COUNT(*) number_of_tasks
      FROM tasks
      WHERE status = "incomplete" 
      GROUP BY userId
      ) t ON u.id = t.userId
    """
    self.cur.execute(query)
    return self.cur.fetchall()

I am doing a simple join for 2 tables. How can I write unit tests for this?

What can I pass in and what kind out output can I check for? In short, what are the best test cases that I could use for unit testing in such a case?

I am using Pytest.

source https://stackoverflow.com/questions/71904763/unit-testing-for-sql-queries