Calculated field
RANK_MODIFIED(SUM([Revenue]))
Compute using: addressing Period; partitioning Region
Sample data
| Region | Period | Revenue | Cost |
|---|---|---|---|
| Harbor | 1 | 120 | 70 |
| Harbor | 2 | 180 | 100 |
| Harbor | 3 | 180 | 120 |
| Harbor | 4 | 240 | 140 |
| Upland | 1 | 90 | 50 |
| Upland | 2 | 150 | 110 |
| Upland | 3 | null | 90 |
| Upland | 4 | 330 | 190 |
The same calculation as SQL
SELECT CAST((CASE WHEN "Revenue" IS NULL THEN NULL ELSE rank() OVER (PARTITION BY "Region" ORDER BY "Revenue" DESC NULLS LAST) + count("Revenue") OVER (PARTITION BY "Region", "Revenue") - 1 END) AS DOUBLE) AS result FROM input ORDER BY "Region", "Period"Runs the example above.
SELECT CAST((CASE WHEN "Revenue" IS NULL THEN NULL ELSE rank() OVER (PARTITION BY "Region" ORDER BY "Revenue" DESC NULLS LAST) + count("Revenue") OVER (PARTITION BY "Region", "Revenue") - 1 END) AS DOUBLE) AS result FROM input ORDER BY "Region", "Period"Written for this dialect; not run here.
SELECT CAST((CASE WHEN `Revenue` IS NULL THEN NULL ELSE rank() OVER (PARTITION BY `Region` ORDER BY `Revenue` DESC NULLS LAST) + count(`Revenue`) OVER (PARTITION BY `Region`, `Revenue`) - 1 END) AS FLOAT64) AS result FROM input ORDER BY `Region`, `Period`
Written for this dialect; not run here.
Result
| Region | Period | Revenue | Cost | result |
|---|---|---|---|---|
| Harbor | 1 | 120 | 70 | 4 |
| Harbor | 2 | 180 | 100 | 3 |
| Harbor | 3 | 180 | 120 | 3 |
| Harbor | 4 | 240 | 140 | 1 |
| Upland | 1 | 90 | 50 | 3 |
| Upland | 2 | 150 | 110 | 2 |
| Upland | 3 | null | 90 | null |
| Upland | 4 | 330 | 190 | 1 |
Same rows from the calculation and from the SQL in DuckDB.
Where a naive translation goes wrong
- Omitting the region partition allows a calculation to consume marks from other regions.
Naive SQL
SELECT CAST((CASE WHEN "Revenue" IS NULL THEN NULL ELSE rank() OVER ( ORDER BY "Revenue" DESC NULLS LAST) + count("Revenue") OVER (PARTITION BY "Revenue") - 1 END) AS DOUBLE) AS result FROM input ORDER BY "Region", "Period"Region Period Revenue Cost result Harbor 1 120 70 6 Harbor 2 180 100 4 Harbor 3 180 120 4 Harbor 4 240 140 2 Upland 1 90 50 7 Upland 2 150 110 5 Upland 3 null 90 null Upland 4 330 190 1 Matches the calculation
SELECT CAST((CASE WHEN "Revenue" IS NULL THEN NULL ELSE rank() OVER (PARTITION BY "Region" ORDER BY "Revenue" DESC NULLS LAST) + count("Revenue") OVER (PARTITION BY "Region", "Revenue") - 1 END) AS DOUBLE) AS result FROM input ORDER BY "Region", "Period"Region Period Revenue Cost result Harbor 1 120 70 4 Harbor 2 180 100 3 Harbor 3 180 120 3 Harbor 4 240 140 1 Upland 1 90 50 3 Upland 2 150 110 2 Upland 3 null 90 null Upland 4 330 190 1
Signature
RANK_MODIFIED(expression, [order])