Obtain the query plan of a running query
Many times a DBA is called to check upon a slow process. Most of the times those processes are running a slow query.
Sometimes it's hard to know if the query is using the best query plan or not. A DBA can reproduce the query, but it it was prepared without values or if the statistics were changed after it started there is no guarantee that the query plan seen by the DBA is the same as the running query.
We have "onstat -g pqs" which sometimes can give us a clue, but it's mostly cryptic and undocumented. If a user has X-Windows he can try xtree, but it's a bit strange for todays standards.
We also have SQLTRACE, but if it was not set when the query was launched it will not capture the info (and besides, due to the circular nature of the buffer it may not be there at the time we need it).
A simple pseudo-table in sysmaster could probably implement this with ease.
It could also be extended to support the "last" query plan making it easy to get the query plan in any tool