When configuring a JDBC connection to an external database in watsonx.data; why is setting appropriate connection pool limits important?

External databases have limited connection capacity; connection pool configuration in the JDBC connector ensures Presto does not open more connections than the database can handle; preventing resource exhaustion on the source system. The incorrect options ("To limit the number of Parquet files written during ETL jobs", "To control the maximum query result size returned to the SQL client", "To ensure the metastore schema is validated before each query") are distractors that don't fully capture the concept described.