new feature: delete user including all other related records

rep_cli.py

@@ -9,6 +9,7 @@ class Session:
         self.resultstring = 'no results yet'
         self.commands = {'a': (self.set_user, 'Set an active user\n   Usage: a number_of_user'),
                          'c': (self.show_composers, 'Shows composers'),
+                         'delete_my_user_record_including_all_mastered_works': (self.delete_user, 'DangerZone: deletes user and all marks of mastered works'),
                          'h': (self.show_help, 'Displays this help document'),
                          'm': (self.mark_work_as_mastered, 'Marks work or movement as mastered for the active user\n   Usage: m number_of_work, m number_of_work number_of_movement'),
                          'n': (self.create_new_user, 'Creates new user\n   Usage: n firstname name'),
@@ -81,6 +82,21 @@ class Session:
         self.db_agent.execute(sql_command)
         return f'Created new user {first_name} {name}.'
 
+    def delete_user(self, _):
+        resultstring = ''
+        if self.user == -1:
+            resultstring += 'Please activate user'
+        else:
+            user_name = self.get_active_user()
+            sql_command = f'''
+                          DELETE FROM pianist
+                          WHERE id = {self.user}
+                          '''
+            self.db_agent.execute(sql_command)
+            resultstring += f'Deleted user {user_name}'
+        return resultstring
+
+
     def show_composers(self, _):
         sql_command = '''
                       SELECT id, first_name, name
@@ -406,6 +422,8 @@ def command_line_loop(session):
 def main():
     con = sqlite3.connect('repertoire.db')
     db_agent = con.cursor()
+    sql_command = 'PRAGMA foreign_keys = ON'
+    db_agent.execute(sql_command)
     session = Session(db_agent)
     command_line_loop(session)
     con.commit()