```json { "classifications": [ { "column": "dataset_id", "role": "identifier", "confidence": 1.0, "reason": "Primary key with unique VARCHAR values (d_00af29bb pattern) identifying each deleted dataset" }, { "column": "tenant_id", "role": "identifier", "confidence": 0.95, "reason": "Foreign key for tenant relationship, currently all NULL but structurally an identifier" }, { "column": "name", "role": "attribute", "confidence": 0.9, "reason": "Descriptive dataset name (e.g., 'Anthropic/EconomicIndex') displayed but not grouped" }, { "column": "source", "role": "dimension", "confidence": 1.0, "reason": "Low-cardinality categorical field (huggingface, kaggle) used for grouping and filtering" }, { "column": "origin_url", "role": "attribute", "confidence": 0.95, "reason": "Descriptive URL displayed for reference, not grouped or aggregated" }, { "column": "created_at", "role": "dimension", "confidence": 1.0, "reason": "Timestamp used for temporal grouping, filtering, and slicing" }, { "column": "deleted_at", "role": "dimension", "confidence": 1.0, "reason": "Timestamp used for temporal grouping, filtering, and slicing" }, { "column": "purged_at", "role": "dimension", "confidence": 1.0, "reason": "Timestamp used for temporal grouping, filtering, and slicing" }, { "column": "table_count", "role": "measure", "confidence": 0.95, "reason": "Numeric quantity (1-5) that would be summed or averaged in aggregations" }, { "column": "total_rows", "role": "measure", "confidence": 1.0, "reason": "Numeric quantity (782-307957) aggregated with sum/avg to analyze dataset sizes" }, { "column": "steps_completed_json", "role": "attribute", "confidence": 0.9, "reason": "JSON array of completed steps, descriptive content displayed but not aggregated" }, { "column": "steps_failed_json", "role": "attribute", "confidence": 0.9, "reason": "JSON array of failed steps, descriptive content displayed but not aggregated" } ] } ```