```json { "classifications": [ {"column": "id", "role": "identifier", "confidence": 1.0, "reason": "Primary key with unique values for each row"}, {"column": "jobs_id", "role": "identifier", "confidence": 1.0, "reason": "Foreign key referencing jobs table"}, {"column": "dataset_id", "role": "identifier", "confidence": 1.0, "reason": "Foreign key referencing dataset with code-like format"}, {"column": "batch_id", "role": "identifier", "confidence": 1.0, "reason": "Foreign key referencing batch with code-like format"}, {"column": "from_tables_catalog_id", "role": "identifier", "confidence": 1.0, "reason": "Foreign key referencing source table in catalog"}, {"column": "from_column", "role": "dimension", "confidence": 0.95, "reason": "Column name used for grouping/filtering relationship analysis"}, {"column": "to_tables_catalog_id", "role": "identifier", "confidence": 1.0, "reason": "Foreign key referencing target table in catalog"}, {"column": "to_column", "role": "dimension", "confidence": 0.95, "reason": "Column name used for grouping/filtering relationship analysis"}, {"column": "confidence", "role": "measure", "confidence": 1.0, "reason": "Numeric score (0-1) representing relationship confidence, aggregatable"}, {"column": "coverage", "role": "measure", "confidence": 1.0, "reason": "Numeric ratio (0-1) representing data coverage, aggregatable"}, {"column": "cardinality", "role": "dimension", "confidence": 1.0, "reason": "Categorical relationship type (1:1, 1:N, N:1) for grouping"}, {"column": "from_distinct", "role": "measure", "confidence": 1.0, "reason": "Numeric count of distinct values in source, aggregatable"}, {"column": "to_distinct", "role": "measure", "confidence": 1.0, "reason": "Numeric count of distinct values in target, aggregatable"}, {"column": "from_null_rate", "role": "measure", "confidence": 1.0, "reason": "Numeric rate (0-1) of null values, aggregatable"}, {"column": "join_viable", "role": "dimension", "confidence": 0.95, "reason": "Binary flag (0/1) indicating join viability, used for filtering"}, {"column": "created_at", "role": "dimension", "confidence": 1.0, "reason": "Timestamp for temporal grouping and filtering"} ] } ```