Somehow I missed there was a DataScript channel there

@jonas: sorted set a much slower to scan by

they use binary tree (red-black), so they have to chase pointers constantly

in btset I have arrays much like vector has

inside array it’s very fast to iterate (chunking)

and most of the queries are index scans

binary lookups and index scans

I lose at almost everything (lookups, insertion, structural sharing percentage) but win a lot on scans

here’s a perf comparison between 0.11.4 and 0.11.5, when I upgraded JVM implementation from sorted-set to BTset

blue and green are “how much times faster”

reds are “how much times slower”

you can see it’s 50-70% slower on conj/disj/lookup

and 400-900% faster on iterate

@tonsky: ok, so it’s for performance reasons. Have you tried to compare perf between clojure’s red-black trees and data.avl?

Logically, representing ‘datoms’ as a sorted set of facts (with different sort orders, such as :avet :eavt etc) is the correct abstraction for implementing datalog? Or is there something missing from the ‘sorted set’ abstraction?

@tonsky one more question (sorry to bother you). Is the benchmark code available somewhere?

@jonas: https://github.com/tonsky/datascript/tree/master/bench

yes, I think it’s the right abstraction

only thing missing from sorted-set is ranges

meaninig, you can find where X is and where Y is inside a set

which data.avl has

but you cannot easily take an iterator from X to Y

great

thanks for the link, I’ll take a look at it later tonight

i'm getting this error:

Uncaught #error {:message "Expected number or lookup ref for entity id, got :artwork.status/sold", :data {:error :entity-id/syntax, :entity-id :artwork.status/sold}}

does datascript support enum?

@sonnyto: are you trying to use :db/ident?

not at the moment

maybe I’ll add support later

for now you can use lookup refs:

[:db/ident <keyword>] instead of <keyword> in place where entity id is expected

Yes. Thanks! Will use keyword instead.

Yes, I found keywords to be much easier to use

Oops misread. OK I'll look into it