When connecting an external PostgreSQL database to watsonx.data; what determines how PostgreSQL data types are mapped to Presto types?

The Presto JDBC connector includes type mapping logic that translates source database types (e.g. PostgreSQL's NUMERIC; TIMESTAMP WITH TIME ZONE) to their Presto equivalents; handling precision and scale differences. The incorrect options ("The user must manually write conversion functions for every column", "PostgreSQL types are always converted to VARCHAR regardless of the original type", "Data type mapping is not needed because Presto and PostgreSQL use identical type systems") are distractors that don't fully capture the concept described.