I need to create a question and answer tables that will have millions (maybe billions) of rows.
The current model is:
Question Table id_question (PK, auto increment) id_user question_content question_date
Answer Table id_answer (PK, auto increment) id_question id_user answer_content answer_date
Is this a correct model (considering better query performance)? Should I add the id_question and id_user columns to the primary key?