Application becomes unresponsive after entering a short query in Athena

[alaq]

Problem

Entering a short query (one or two characters) in Athena will freeze the application. The only way out of it is to close the tab. You need to have data for this.

Expected Behavior

The application should remain responsive and show a list of results in Athena.

Dependencies

• Athens: latest master
• browser: Chromium, Firefox

To Reproduce

https://athensresearch.github.io/athens/ then load test data, input one or two characters in Athena. The application will freeze.

[jorda0mega]

the main issue is with the get-root-parent-node function in db.cljs. After loading the Test DB, if you type "a" the search-in-block-content function will return 1780 records. Looping through all of the children blocks of 1780 records will freeze the application. A possible solution would be to limit the query results to 20 to begin with. The code is already limiting the search results to 20 in athena.cljs

(defn get-root-parent-node
  [block]
  (loop [b block]
    (if (:node/title b)
      (assoc block :block/parent b)
      (recur (first (:block/_children b))))))

[itsrainingmani]

@jorda0mega I think datascript has a :limit option that should allow us to limit how many search queries are returned. I'm going to test that and see what the best option is.

[jorda0mega]

So I tried the :limit in datomic pull syntax but that's only for a many attribute. In this case I think we would need the cap the entire list of results rather than one of the attributes. Might be wrong though so let me know if it works

[itsrainingmani]

I also tried just putting a (take 20) inside the search-in-block-content which seems to fix this issue. There is still some latency though.

https://github.com/itsrainingmani/athens/blob/a0ac5c37b9c80f117c21cb422fe98674953fc4e3/src/cljs/athens/db.cljs#L305

[jorda0mega]

Nice. That's what I was thinking as well but I feel there has to be a way to do this at the query level

[itsrainingmani]

I looked at the datascript source and I can't find an option for that. So maybe not.

[tangjeff0]

@jorda0mega I don't believe there is! The datalog query is set-based, so if there was a native limit within the query, I think it would essentially be doing the same thing as take outside the query. Different from the typical mental model of SQL dbs!