Re: Multiple elements condition

> exists(para[2]) and not(exists(para[3]))
> 
> or
> 
> exists(para[2]) and empty(para[3])

they both always look for the 2nd and 3rd element but you don't need t0
look for the 3rd if the 2nd isn't there....

if (para[2]) then empty(para[3]) else false()

but the chance that any of these make a measurable difference is slim,

Although the original versions with count() could be noticably slower
if the system doesn't rewrite it away. same is true  in theory for these
of course. According to the spec  one might expect that para[1] is just
as likely to access all 10000 para elements (and then filter out all but
the first) as count(para)=1. But it's probbaly more likely that numeric
filters are optimised.

David

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