The Quack Client/Server Protocol for DuckDB

Quack is released as a pre-release extension and is currently experimental. If you encounter any issues, please file them via GitHub.

The quack extension adds a client-server protocol to DuckDB. With this extension, DuckDB can act as both a server and a client to communicate over a network. For more details, please see the announcement page, the blog post and the documentation.

Usage Example

We have to install the extension in all involved DuckDB instances:

INSTALL quack FROM core_nightly;

Then, we can use one DuckDB instance as a server like so:

LOAD quack;
CALL quack_serve('quack:localhost', token = 'super_secret');
CREATE TABLE hello AS FROM VALUES ('world') v(s);

And talk to this server from another instance:

LOAD quack;
CREATE SECRET (TYPE quack, TOKEN 'super_secret');
ATTACH 'quack:localhost' AS remote;
FROM remote.hello;

This should show the content of the remote table hello on the client side.

We can also copy data from client to server:

-- on client
CREATE TABLE remote.hello2 AS FROM VALUES ('world2')v(s);

-- on server
FROM hello2;

Development

Managing dependencies

DuckDB extensions uses VCPKG for dependency management. Enabling VCPKG via the provided makefile target:

make setup-vcpkg
export VCPKG_TOOLCHAIN_PATH=`pwd`/vcpkg/scripts/buildsystems/vcpkg.cmake

Build steps

Now to build the extension, run:

make

The main binaries that will be built are:

./build/release/duckdb
./build/release/test/unittest
./build/release/extension/quack/quack.duckdb_extension

• duckdb is the binary for the duckdb shell with the extension code automatically loaded.
• unittest is the test runner of duckdb. Again, the extension is already linked into the binary.
• quack.duckdb_extension is the loadable binary as it would be distributed.

Running the tests

Different tests can be created for DuckDB extensions. The primary way of testing DuckDB extensions should be the SQL tests in ./test/sql. These SQL tests can be run using:

make test