The following are guidelines that you should take into account when implementing Collaborative Planning:
- Look at Collaborative Planning as a question-answer session.
Do not provide an answer to the question that was not asked.
- Provide simple intuitive responses, as shown in the following table.
Simple intuitive responses Request by Planner Response by SQL-MapReduce Function Input Distribution Output Distribution Input Order Output Order Predicates Classified predicates Order + Limit Y/N Output column projection Y/N Input column projection
- During predicate planning phase of Collaborative Planning, an Aster instance normalizes the constants used in predicates before sending them in the predicate message in CollaborativePlanningRequest.
When normalizing a predicate for a bigint value such as -9223372036854775809 (-1 greater than the largest negative bigint value), the value is upcast to numeric. However, the numeric value shows some loss in precision. In this case, the Collaborative Planning request shows a numeric value of -9223372036850000000.