So what is the right way for performing a fast aggregation and grouping? Search views?
-- Andreas Jung From: Jan <[email protected]>(mailto:[email protected]) Reply: [email protected] <[email protected]>(mailto:[email protected]) Date: 20. May 2019 at 08:39:47 To: ArangoDB <[email protected]>(mailto:[email protected]) Subject: [arangodb-google] Re: Index not used for query > Hi, > > as of ArangoDB 3.4, `RETURN DISTINCT` (which is turned into a `COLLECT` > statement by the optimizer) is not able to make use of indexes. > The same is true for any other form of `COLLECT`. Indexes will be used for > filtering and sorting, but right now they are not used for any sort of > aggregation. > > Best regards > Jan > > Am Sonntag, 19. Mai 2019 15:29:45 UTC+2 schrieb Andreas Jung: > > Running ArangoDB 3.4.5 on a collection with 100.000 items. > > Each item has singe-valued field _type and there are about 20 different > > values for this field. > > The field is indexed by a hash index: https://nimb.ws/yh4rRb > > > > This query performs a full table scan instead of using the index. > > Am I missing something here? > > > > For doc in import > > return distinct doc._type > > > > Query String: > > For doc in import > > return distinct doc._type > > > > Execution plan: > > Id NodeType Est. Comment > > 1 SingletonNode 1 * ROOT > > 2 EnumerateCollectionNode 95238 - FOR doc IN import /* full collection > > scan, projections: `_type` */ > > 3 CalculationNode 95238 - LET #1 = doc.`_type` /* attribute expression */ > > /* collections used: doc : import */ > > 4 CollectNode 76190 - COLLECT #3 = #1 /* distinct */ > > 5 ReturnNode 76190 - RETURN #3 > > > > Indexes used: > > none > > > > Optimization rules applied: > > Id RuleName > > 1 reduce-extraction-to-projection > > > > > > > -- > You received this message because you are subscribed to the Google Groups > "ArangoDB" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to > [email protected](mailto:[email protected]). > To view this discussion on the web visit > https://groups.google.com/d/msgid/arangodb/2c5efa6f-f1e6-4db9-8f18-07e19997e92e%40googlegroups.com(https://groups.google.com/d/msgid/arangodb/2c5efa6f-f1e6-4db9-8f18-07e19997e92e%40googlegroups.com?utm_medium=email&utm_source=footer). > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "ArangoDB" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/arangodb/etPan.5ce24c5b.74b0dc51.17e8%40gmail.com. For more options, visit https://groups.google.com/d/optout.
