Support Dynamic Type in ifNull and coalesce Functions

Why it matters

This feature enables the ifNull and coalesce functions to handle columns or expressions of the Dynamic data type, allowing users to work seamlessly with nullable dynamic data structures and improve flexibility when managing JSON-like data.

How to use it

Users can directly use the ifNull and coalesce functions with Dynamic type arguments in their SQL queries without any additional configuration. Example usage:

SELECT ifNull(dynamic_column, '{}'::Dynamic) FROM table;
SELECT coalesce(dynamic_column1, dynamic_column2, '{}'::Dynamic) FROM table;