Hi Adam,
EnableSkipStargate is an undocumented MDX keyword (read: nothing specific/related to REST API). As the name suggests it allows the requester to hint the TM1 server to bypass the creation of a stargate in certain cases (note: queries with NON EMPTY clauses or straight cross joins on all axes will always use a stargate despite this hint;-) as it deems that it would be more efficient to go after the requested views in the result one by one vs building a symmetric cross join that would contain all those cells.
Note that in the majority of cases it would be more efficient to create a cross join and the build-in heuristics would typically otherwise be smart enough to bypass it but it was found that PAfE specifically creates edge cases for this in which hinting the server to not bother was beneficial for performance.
Wrt 'caching', stargates are first and foremost created for performance reasons. Depending on the time it took to create them and the amount of memory available (read: VMM and VMT options) they are optionally retained in cache for potential later reuse as well. I.o.w. the EnableSkipStargate is intended to bypass the optimization, not the cache;-).
PS Note that we are internally working on future versions of the query engine in which this hint will become completely obsolete again and therefore the flag being removed once again. If in the meantime you feel you have cases where using this hint could be beneficial by all means go ahead and do so;-!
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Hubert Heijkers
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