MAP_TRANSFORM_KEYS
Applies a transformation to each key in a map using a lambda expression.
SQL Syntax
MAP_TRANSFORM_KEYS(<map>, (<key>, <value>) -> <key_transformation>)
Return Type
Returns a map with the same values as the input map but with keys modified according to the specified lambda transformation.
SQL Examples
This example adds 1,000 to each product ID, creating a new map with updated keys while keeping the associated prices the same:
SELECT MAP_TRANSFORM_KEYS({101: 29.99, 102: 45.50, 103: 15.00}, (product_id, price) -> product_id + 1000) AS updated_product_ids;
┌────────────────────────────────────┐
│ updated_product_ids │
├────────────────────────────────────┤
│ {1101:29.99,1102:45.50,1103:15.00} │
└────────────────────────────────────┘