Customization challenges

# Challenge 1: Add a "Query History" Agent
# Store and retrieve previous queries for the session

class AgentState(TypedDict):
    # ... existing fields ...
    query_history: list  # Add this field

def history_agent(state: AgentState) -> AgentState:
    """Store successful queries in history"""
    history = state.get("query_history", [])
    if state["sql_query"] and not state["error"]:
        history.append({
            "question": state["question"],
            "sql": state["sql_query"],
            "timestamp": datetime.now().isoformat()
        })
    state["query_history"] = history[-10:]  # Keep last 10
    return state

# Challenge 2: Add Query Caching
# Cache repeated queries to avoid redundant LLM calls

from functools import lru_cache
import hashlib

@lru_cache(maxsize=100)
def cached_sql_generation(question_hash: str, question: str) -> str:
    """Cache SQL generation for repeated questions"""
    # Your SQL generation logic here
    pass

def sql_agent_with_cache(state: AgentState) -> AgentState:
    question = state["question"]
    question_hash = hashlib.md5(question.lower().encode()).hexdigest()

    # Try cache first
    cached = cached_sql_generation(question_hash, question)
    if cached:
        state["sql_query"] = cached
        state["sql_reason"] = "Retrieved from cache"
        return state

    # Otherwise generate new SQL
    # ... existing logic ...