use polars and duckdb for lazy processing

src/app/vinyl/assets.py

@@ -2,7 +2,6 @@ from datetime import datetime
 from glob import glob
 
 import duckdb
-import pandas as pd
 import polars as pl
 import structlog
 from duckdb.typing import DATE, VARCHAR
@@ -110,17 +109,13 @@ def deals(context):
     )
 
 
-@asset(deps=[deals], io_manager_key="duckdb_io_manager")
-def new_deals(
-    context: OpExecutionContext,
-    # duckdb: DuckDBResource
-) -> pd.DataFrame:
+@asset(deps=[deals], io_manager_key="polars_parquet_io_manager")
+def new_deals(context: OpExecutionContext) -> pl.DataFrame:
     ic()
     storage_dir = context.instance.storage_directory()
     asset_key = "deals"
 
     with duckdb.connect() as con:
-        # with duckdb.get_connection() as con:
         con.create_function("PARSE_DATE", parse_date, [VARCHAR], DATE)
         return con.execute(
             f"""
@@ -167,16 +162,20 @@ def new_deals(
             WHERE rn = 1
             ORDER BY date ASC
             """
-        ).df()
+        ).pl()
 
 
 @asset(
-    # deps=[new_deals],
-    io_manager_key="duckdb_io_manager"
+    io_manager_key="polars_parquet_io_manager",
 )
-def works(new_deals: pd.DataFrame) -> pd.DataFrame:
-    return new_deals[["artist", "title"]].drop_duplicates()
-    # with duckdb.get_connection() as con:
-    #     return con.execute(
-    #         "SELECT DISTINCT artist, title, release FROM vinyl.public.new_deals"
-    #     ).df()
+def works(new_deals: pl.DataFrame) -> pl.DataFrame:
+    # Pandas
+    # columns = ["artist", "title"]
+    # return pl.from_pandas(new_deals[columns].to_pandas().drop_duplicates())
+
+    # Polars
+    # return new_deals[columns].unique(subset=columns)
+
+    # DuckDB
+    with duckdb.connect() as con:
+        return con.execute("SELECT DISTINCT artist, title, release FROM new_deals").pl()

src/app/vinyl/repo.py

@@ -23,8 +23,7 @@ vinyl = Definitions(
     assets=[deals, new_deals, works],
     resources={
         "polars_parquet_io_manager": PolarsParquetIOManager(),
-        "duckdb_io_manager": PandasDuckDBIOManager(database="vinyl.duckdb"),
-        # "duckdb": DuckDBResource(database="vinyl.duckdb")
+        "duckdb_io_manager": PandasDuckDBIOManager(database="vinyl"),
     },
     jobs=[deals_job, check_partititions_job, musicbrainz_lookup_job],
     schedules=[deals_schedule],