Port DuckDB from the langchain python package to the langchain js package.

[cdierkens]

Checked

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Feature request

Port all of the DuckDB code and documentation to the TypeScript package from the Python code.

Motivation

DuckDB is an in process database that will allow embedded use cases of Langchain.

Proposal (If applicable)

I will follow up with a PR that includes all the DuckDB related files and link it to the discussion.

[cdierkens]

Note: The python docs are located in a notebook. Will probably convert to plain mdx as opposed to Deno notebooks.

[cdierkens]

Main Files

Vector Store

Document Loader

[cdierkens]

Nice to Have

• Message History Interface

[cdierkens]

Possible starting point: https://github.com/langchain-ai/langchainjs/blob/main/libs/langchain-community/src/stores/message/postgres.ts