I am looking to dump from results of the SQL Executor into a DB table (fields not known). Looking for ways to do it. I see there is Schema and Result port for SQLExecutor. Not sure how to use both in order to insert the data into a table.

Probably the easiest way would be to do it all in the SQLExecutor, to use a statement like Select * into new_table from other_table. That'll write the results (whatever they are) into a new db table. Keeping it all on the database is nice and simple.

To get the same effect with a writer in FME, a SQL FeatureReader can be set to read 'schema and data features', then you'll need to learn about dynamic writing, but basically the schema feature can be used to tell a writer set to 'dynamic' what its output schema will be.

https://community.safe.com/s/article/dynamic-workflow-tutorial-introduction