praveenc7 opened a new pull request, #16678: URL: https://github.com/apache/pinot/pull/16678
# ANY_VALUE Aggregation Function ## Overview The `ANY_VALUE` aggregation function returns any arbitrary value from the specified column for each group in a `GROUP BY` query. This function is particularly useful for optimizing queries where you need to include a column in the `SELECT` clause that has a 1:1 mapping with the `GROUP BY` columns, without forcing that column into the `GROUP BY` clause. ## Syntax ```sql ANY_VALUE(column_name) ``` ## Use Cases ### Primary Use Case: Avoiding Unnecessary GROUP BY Columns Standard SQL requires that all non-aggregation expressions in the `SELECT` clause must also be part of the `GROUP BY` clause. However, there are scenarios where: 1. **Functional Dependency**: A column has a 1:1 mapping with the grouped columns 2. **Performance Optimization**: Adding the column to `GROUP BY` would increase computation without changing the logical result 3. **Query Simplification**: You want to display related data without affecting grouping behavior ### Example Scenario Consider an `ORDERS` table with `CustomerID`, `CustomerName`, and `OrderValue`: **Without ANY_VALUE (Standard SQL):** ```sql -- Option 1: Add CustomerName to GROUP BY (more computation) SELECT CustomerID, CustomerName, SUM(OrderValue) FROM Orders GROUP BY CustomerID, CustomerName; -- Option 2: Remove CustomerName from SELECT (lose information) SELECT CustomerID, SUM(OrderValue) FROM Orders GROUP BY CustomerID; ``` **With ANY_VALUE (Optimized):** ```sql -- Get CustomerName without adding to GROUP BY SELECT CustomerID, ANY_VALUE(CustomerName), SUM(OrderValue) FROM Orders GROUP BY CustomerID; ``` ## Behavior - **Returns**: Any arbitrary value from the column for each group - **Null Handling**: Supports both null-handling enabled and disabled modes - **Data Types**: Works with all Pinot data types (INT, LONG, FLOAT, DOUBLE, STRING, BYTES, BIG_DECIMAL) - **Performance**: More efficient than adding the column to `GROUP BY` when there's a 1:1 mapping -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
