```json { "table_name": "Iris", "primary_key": "Id", "candidates": [ { "rank": 0, "partition_key": "Species", "partition_key_label": "primary_identifier", "partition_key_reasoning": "Species has RPUV=50.00 (3 unique values, 50 rows each), providing balanced partitioning for this botanical reference dataset. Top 3 Coverage=100% with equal distribution across three iris species. Semantically serves as the natural categorical organizer for flower measurements.", "clustering_key": "Id", "clustering_key_label": null, "clustering_key_reasoning": "Id is the unique identifier with RPUV=1.00, perfect monotonicity=1.000, and serves as the primary key. While dimension tables typically don't need clustering, Id provides deterministic ordering within each species partition.", "world_line": null, "session_column": null, "confidence": "HIGH", "notes": "This is the classic Iris dataset - a dimension table of botanical measurements. Species is the natural partition key (3 balanced groups of 50). Id is the primary key. The measurement columns (SepalLengthCm, SepalWidthCm, PetalLengthCm, PetalWidthCm) are attributes. Metadata columns (_ingestion_timestamp, _batch_id, _source_file, _source_system) all have RPUV=150 (single value) and are not suitable for partitioning." } ] } ```