Benchmarking Results: Internal vs External Table in Oracle Autonomous Data warehouse with 1 Billion Records
In this benchmarking test, the objective was to compare the query performance between an internal relational table and an external table (created from a Parquet file in OCI Object Storage) in Oracle ADW The Parquet file contained 1 billion records, and the same data was loaded into both an internal ADW table and an external table using the Parquet file as the data source. Queries were executed using SQL Developer SET TIMING ON; -- Query to count rows in the internal table SELECT COUNT(*) FROM internal_table; -- Query to count rows in the external table (Parquet-based) SELECT COUNT(*) FROM BIG_EXTERNAL_TABLE; Execution Plans Internal Table Execution Plan: • Operation: TABLE ACCESS STORAGE FULL — Oracle retrieves data directly from its optimized storage. • resourceCost: 4329 • Result Cache: Enabled, allowing Oracle to cache the result for faster retrieval in subsequent queries. • Parallelism: Automat...