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braai engineer 2025-06-10T08:40:26.581479Z
Why am I getting output from d/datoms for a tuple attribute, but no results when using d/index-range on the tuple, when using in-memory On Prem?
I'm passing values that I know exist based on d/datoms:
(into [] (d/datoms db :avet :eacl.permission/resource-type+permission-name))
=> [#datom[17592186045426 96 [:account :admin] 13194139534313 true]
#datom[17592186045427 96 [:account :view] 13194139534313 true]
...]
(into [] (d/index-range db :eacl.permission/resource-type+permission-name [:account :admin] [:account :admin]))
=> []braai engineer 2025-06-10T08:47:20.688259Z
Ah, I see that end is exclusive. I'm getting output for this:
(into [] (d/index-range db :eacl.permission/resource-type+permission-name [:account :admin] nil)) => resultsnil, or
(into [] (d/index-range db :eacl.permission/resource-type+permission-name [:account :admin] [:server nil])) => results(into [] (d/index-range db :eacl.permission/resource-type+permission-name [:account :admin] [:account nil])) => []index-range if there's only one value for the starting key?braai engineer 2025-06-10T08:48:05.860309Z
Surprised I can't do this:
(into [] (d/index-range db :eacl.permission/resource-type+permission-name [:account :admin] [nil nil]))
favila 2025-06-10T12:42:03.091969Z
Just take-while
favila 2025-06-10T19:10:20.621699Z
reason nil doesn't work as an end is it sorts lower than any other value. It's not understood as a "no limit" sentinel unless the entire end argument is nil
favila 2025-06-10T19:12:37.013119Z
(sequence
(take-while (fn [datom] (= [:account :admin] (:v datom))))
(d/index-range db :eacl.permission/resource-type+permission-name [:account :admin] nil)
)👍 1
favila 2025-06-10T19:13:06.140019Z
d/datom would work fine for this simple case also
favila 2025-06-10T19:13:26.034489Z
(d/datoms db :avet :eacl.permission/resource-type+permission-name [:account :admin])braai engineer 2025-06-10T19:14:10.135279Z
benchmarked d/datoms vs d/seek-datoms and was surprised that d/datoms was ~10x faster via criterium (we’re talking nano & milliseconds here)
favila 2025-06-10T19:16:28.610199Z
seek-datoms?
favila 2025-06-10T19:16:39.623009Z
were you comparing equivalent things?
braai engineer 2025-06-10T19:19:20.778259Z
this was the last benchmark I ran:
(quick-bench
(first (d/datoms (d/db conn) :avet :eacl.relationship/subject+relation-name+resource
[(:db/id super-user) :super_admin (:db/id platform)])))(quick-bench
(first (d/seek-datoms (d/db conn) :avet :eacl.relationship/subject+relation-name+resource
[(:db/id super-user) :super_admin (:db/id platform)])))d/seek-datoms is chunkingfavila 2025-06-10T19:19:49.258959Z
seek-datoms does not terminate
👍 1
braai engineer 2025-06-10T19:19:56.048459Z
ahh
favila 2025-06-10T19:20:07.469339Z
there's no guarantee that first item matches your parameters
favila 2025-06-10T19:20:24.005749Z
this is also mostly measuring setup costs, not the cost of scanning
favila 2025-06-10T19:22:10.532909Z
docstring for seek-datoms: https://docs.datomic.com/clojure/index.html#datomic.api/seek-datoms
vc 2025-06-10T18:29:49.294579Z
what is the standard practice to enforce right-to-be-forgotten in datomic?
favila 2025-06-10T19:08:22.616829Z
there are two:
favila 2025-06-10T19:08:36.529939Z
1. use excision (datomic pro only)
❤️ 1
favila 2025-06-10T19:09:09.309679Z
2. use a supplemental storage for PII that supports delete, store a pointer in datomic.
vc 2025-06-10T20:00:50.457259Z
Thanks. Had no idea excision was there. Didn't come across in docs neither (as usual) gpt revealed it.
Sven 2025-06-10T20:30:47.650059Z
> 1. use excision (datomic pro only) Any plans of supporting it in Cloud?
favila 2025-06-10T20:31:29.595409Z
not ruled out, but no concrete plans to add right now
😢 2
✅ 1