ducklake-java

A java implementation of ducklake. This project is still under development.

Java version

Java 17 or above is required.

examples

Snapshot

    public static void main(String[] args) {
        // You can use the following command to start a postgres instance for testing.
        // `docker run -d \
        //  -e POSTGRES_USER=test \
        //  -e POSTGRES_PASSWORD=test \
        //  -e POSTGRES_DB=ducklake_catalog \
        //  -p 5432:5432 \
        //  --name postgres \
        //  postgres:16-alpine`
        
        // You can also use other metadata catalogs, such as MySQLMetadataCatalogImpl, DuckDBMetadataCatalogImpl, etc.
        BaseMetadataCatalog catalog = new PostgresMetadataCatalogImpl("ducklake_catalog",
                                                                      "localhost",
                                                                      5432,
                                                                      "test",
                                                                      "test",
                                                                      ".tmp/data_files/");
        // After initializing, the catalog will be ready to use. You can query the metadata tables from the postgres instance.
        catalog.initialize();
        Snapshot snapshot = catalog.getSnapshot(null);
        System.out.println("--------------------------------");
        System.out.println("snapshot:\n" + snapshot);
        System.out.println("--------------------------------");
        System.out.println("table:\n" + catalog.getTable(snapshot.id(), new TableIdentifier("a")));
        System.out.println("--------------------------------");
        catalog.close();
    }