Dear all, While playing around with the HepPlanner I ran into an issue where the planner wants to rewrite a query with a union rewrite. When the RelMetaDataQuery computes the cost, the cost instance is a VolcanoCost. Then when it tries to calculate the cost of one of the union's operands it is a RelCostImpl which results in the ClassCastException.
How would I go about solving this issue? As far as my knowledge goes, I am not able to change the costhandler of the RelMetaDataQuery. Another approach I could see is removing the cast in the VolcanoCost class, but I would hope I do not have to do that. With kind regards, Mark
