Add query checker to db chain

app.py

@@ -78,7 +78,8 @@ def answer_question(query):
     db_chain = SQLDatabaseChain.from_llm(llm, db, 
                                          prompt=PROMPT, 
                                          verbose=True, 
-                                         return_intermediate_steps=True
+                                         return_intermediate_steps=True,
+                                         use_query_checker=True
                                          )
     result = db_chain(q)
     return result['result']