I wish to estimate the total cost for a given path of a query. This path is a tree consists of nestloop, hashjoin, mergejoin as internal nodes with seqscan or idxscan at the leaves.
My approach is to cost the path bottom-up, and invoke the "cost_nestloop", "cost_merge_join" etc. The problem is that each join method has some value that seems to change value each time I cost the SAME path. For example, the hash-join has "thisbucketsize" varying from time to time. I noticed this is because the caching the bucket size estimate inside the RestrictInfo structure. Is there a easy way to cost a give path? ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
