So, the PATH function is Oracle specific? Or your own proposal?
Match PATH is essentially the internal metadata or the trace log of which
Row Pattern Variable (Classifier) was assigned to each row during the
state machine's execution.
Match PATH is simply a set of Classifiers stored in the internal state.
> I trust that you will help define the strategic roadmap for these releases. > As I continue to > deepen my understanding of the standard, I will do my best to contribute to > the > technical roadmap as well.
Ok, here is my proposal for the strategic roadmap. This should be a starting point of the discussion.
(1) The first release: this will a subset of R020 (RPR in Window clause), but will serve many of pratical uses of RPR. The following features below will not be included.
- MEASURES - SUBSET - SEEK - AFTER MATCH SKIP TO - AFTER MATCH SKIP TO FIRST - AFTER MATCH SKIP TO LAST - PERMUTE
Note 1: this list needs discussion and may be changed when the release is made.
Note 2: Because MEASURES cannot be used in this release, all primary row patter variables in the DEFINE clause must be unqualified ones (i.e. "price", not "A.price") and they are implicitly qualified by the universal row pattern variable. In this case the universal row pattern variable is mapped to the current row, thus "price" in the DEFINE clause is evaluated in the current row.
After (1) we can choose either (a) extend support for R020, i.e. add more features to the first release, especially MEASURES or (b) support a subset of R010 (MATCH_RECOGNIZE).
I am currently fixing the code to satisfy the existing test cases.
Once the modifications are complete, I'll share the details so we can
discuss the differences between the current status and the proposed
