Efficiently Query Large Parquet Files in Python Using DuckDB
Query large Parquet files directly in Python using DuckDB's SQL interface, avoiding memory errors associated with loading entire datasets into Pandas.
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Query large Parquet files directly in Python using DuckDB's SQL interface, avoiding memory errors associated with loading entire datasets into Pandas.
DuckDB can read Parquet files directly with SQL, pushing filters into the file reader for ad-hoc analytics without an ETL load step.
Query Parquet files on disk with DuckDB's read_parquet, using column projection and predicate pushdown to read only what your SQL needs.
A decision guide for choosing between DuckDB's native .db storage and Apache Parquet, focusing on ACID compliance, I/O performance, and data portability.
Learn how to write query results to a Hive-style partitioned Parquet dataset using DuckDB's COPY TO, validate the output, and recover from common write failures.
DuckDB's read_parquet lets you query Parquet lakes without ETL, but per-query metadata overhead and schema drift have real costs. Here's how to decide.
DuckDB’s vectorized engine and Parquet push‑down cut CPU work and I/O for analytical scans, as shown in a step‑by‑step example that creates a 100‑million‑row Parquet file, runs a filtered aggregation, and verifies push‑down with EXPLAIN.
DuckDB's built-in Parquet extension lets you read and write columnar files directly from SQL with automatic predicate push-down and partitioning—no Spark cluster required. Here's the practical map for engineers moving data in pipelines.
Learn how DuckDB lets you read, transform, and write Parquet files directly from SQL without extra services or complex setup.