Motherduck is a managed DuckDB-in-the-cloud service.

​
Installation and Setup

First, you need to install duckdb python package. 
pip install duckdb
You will also need to sign up for an account at Motherduck After that, you should set up a connection string - we mostly integrate with Motherduck through SQLAlchemy. The connection string is likely in the form: 
token="..."

conn_str = f"duckdb:///md:{token}@my_db"

​
SQLChain

You can use the SQLChain to query data in your Motherduck instance in natural language. 
from langchain_openai import OpenAI
from langchain_community.utilities import SQLDatabase
from langchain_experimental.sql import SQLDatabaseChain
db = SQLDatabase.from_uri(conn_str)
db_chain = SQLDatabaseChain.from_llm(OpenAI(temperature=0), db, verbose=True)
From here, see the SQL Chain documentation on how to use.

​
LLMCache

You can also easily use Motherduck to cache LLM requests. Once again this is done through the SQLAlchemy wrapper. 
import sqlalchemy
from langchain.globals import set_llm_cache
eng = sqlalchemy.create_engine(conn_str)
set_llm_cache(SQLAlchemyCache(engine=eng))
From here, see the LLM Caching documentation on how to use.