[basex-talk] Internal cache for often accessed node sets?

Hello,

thanks to the all the answers I received in the thread "Optimization of a slow query with `//`" I can now make most of my queries much faster. However, while rewriting these queries I noticed that almost all the queries in my application could be rewritten in the form

/tei:TEI/tei:text/tei:body//tei:ELEM[PREDICATE]

and I wondered if it was possible to tell BaseX (or to have it understand by itself) that it can cache and reuse the results of

/tei:TEI/tei:text/tei:body//tei:ELEM

and only apply PREDICATE on the saved set of results.

Is something like this available in BaseX?

I suppose this could have a big impact on my queries, because the base query executes in about 250 ms and most of the other unoptimized queries in about 280 ms. This means that with the case in place they should complete in 30 ms (or 50 ms in more realistic terms).

I tried sending via HTTP a dummy request for `/tei:TEI/tei:text/tei:body//tei:ELEM` together with a `<option name='cachequery' value='true'/>` to warm up the cache. Unfortunately all I got back was a "Unknown option 'CACHEQUERY'" error (with BaseX 8.2.1). Any idea why?

Regards,

-- Gioele Barabucci gioele@svario.it