Lineage Granularity: Table vs Column vs Row Level Trade-offs

Table Level Lineage
Lineage granularity determines what you can trace and at what cost. Table level lineage tracks dependencies between datasets as whole units, answering which tables feed into which downstream tables. This is cheap to collect and query, scaling to millions of tables with minimal overhead, but provides only coarse impact analysis. If an upstream table schema changes, you know all downstream tables are affected but not which specific columns or rows break.
Column Level Lineage
Column level lineage maps individual columns through transformations, tracking that output column revenue depends on input columns price and quantity through a multiplication. This enables precise schema evolution safety. When renaming or dropping a column, you see exactly which downstream columns lose their inputs. The overhead is moderate: metadata size grows with column count times transformation fan out, and collection requires parsing query plans or instrumenting data frames to track column projections. At enterprise scale with thousands of tables averaging 50 columns each, this still remains tractable at tens of millions of edges.
Row Level Lineage
Row level lineage traces individual output rows back to the specific input rows that produced them, essential for auditing PII flows or right to be forgotten compliance. The cost is severe: storage inflates 5 to 20 times because you maintain per row mappings, and compute overhead doubles as joins must track provenance vectors.
Practical Strategy
Reserve row level lineage for subsets flagged by policy, such as financial transactions or medical records, or use sampling to trace a representative 1 to 10 percent of rows for debugging rather than full coverage.

💡 Key Takeaways

✓Table level lineage provides coarse impact analysis at minimal cost, scaling to millions of datasets but only identifying affected downstream tables without column or row specificity

✓Column level lineage enables precise schema evolution by mapping which output columns derive from which inputs, adding moderate metadata overhead proportional to column count times transformation fan out

✓Row level lineage traces individual output rows to specific input rows, inflating storage 5 to 20 times and doubling compute costs by maintaining per row provenance vectors through joins

✓Enterprise lineage graphs with thousands of tables and 50 columns average reach tens of millions of column level edges, remaining queryable under 500 milliseconds with denormalized indexes

✓Pragmatic approach uses table level by default, column level for governed datasets and schema evolution sensitive pipelines, and row level selectively for regulated data or sampled at 1 to 10% for debugging

📌 Interview Tips

1Uber tracks column level lineage for feature definitions, enabling impact analysis when raw event schemas evolve; renaming a field shows exactly which 37 downstream features require transformation updates

2Healthcare data warehouse implements row level lineage for patient records to support right to be forgotten requests, storing per row mappings that inflate storage from 2 terabytes to 18 terabytes for full audit trail

3E-commerce platform uses table level lineage for 5,000 datasets, column level for 200 revenue critical tables, and row level sampling at 5% for debugging recommendation pipeline issues without full overhead

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