```json { "classifications": [ { "column": "id", "role": "identifier", "confidence": 1.0, "reason": "Primary key with unique BIGINT values for each row" }, { "column": "consumer", "role": "dimension", "confidence": 1.0, "reason": "Low cardinality (7 values) categorical field for grouping/filtering by consumer type" }, { "column": "consumer_kind", "role": "dimension", "confidence": 1.0, "reason": "Very low cardinality (2 values) categorical field for grouping by consumer kind" }, { "column": "dataset_id", "role": "identifier", "confidence": 1.0, "reason": "Foreign key reference to dataset, used for joining tables" }, { "column": "batch_id", "role": "identifier", "confidence": 1.0, "reason": "Foreign key reference to batch, used for joining tables" }, { "column": "table_name", "role": "dimension", "confidence": 0.95, "reason": "Medium cardinality (286 values) categorical field for grouping/filtering by table" }, { "column": "column_name", "role": "dimension", "confidence": 0.9, "reason": "Higher cardinality (2367 values) but still used for grouping/filtering by column" }, { "column": "family", "role": "dimension", "confidence": 1.0, "reason": "Very low cardinality (4 values) categorical field for grouping by tag family" }, { "column": "tag", "role": "dimension", "confidence": 1.0, "reason": "Low cardinality (7 values) categorical field for grouping/filtering by tag type" }, { "column": "first_seen_at", "role": "dimension", "confidence": 1.0, "reason": "Timestamp field used for temporal filtering and grouping" }, { "column": "last_seen_at", "role": "dimension", "confidence": 1.0, "reason": "Timestamp field used for temporal filtering and grouping" }, { "column": "hit_count", "role": "measure", "confidence": 1.0, "reason": "Numeric quantity to be aggregated (sum/avg) representing count of hits" } ] } ```