Hi,
I need your help!
I am try to query my db using two different queries.
the first is:
FOR doc1 in catalogue
FOR doc2 in RepoNodes
FILTER doc1.trackid>= "TRAAAAK128F9318786" AND doc1.trackid<=
"TRAACER128F4290F96" AND doc1.trackid==doc2.mongodbsongs
FOR doc3 in RepoEdges
FILTER doc3._from==doc2._id
FOR doc4 in RepoNodes
FILTER doc3._to ==doc4._id
FOR doc5 in RepoEdges
FILTER doc5._from==doc4._id
FOR doc6 in RepoNodes
FILTER doc6._id ==doc5._to
FOR doc7 in RepoEdges
FILTER doc7._from==doc6._id
FOR doc8 in RepoNodes
FILTER doc8._id ==doc7._to
FOR doc10 in catalogue
FILTER doc10.trackid== doc8.mongodbsongs
FOR doc11 in similarities
FILTER doc11._from==CONCAT("Tracks/",doc8.neo4jSong)
FOR doc12 in clearance
FILTER doc8.redisclearance== doc12._key
return {doc10,doc11,doc12}
where I apply Filters a lot of times, and it's ok, because I can get
results and the search uses Indexes..
In the explain of this I see:
1 SingletonNode 1 * ROOT
45 IndexNode 111882 - FOR doc1 IN catalogue /*
skiplist index scan */
44 IndexNode 4693561782 - FOR doc2 IN RepoNodes /*
skiplist index scan */
46 CalculationNode 4693561782 - LET #11 =
((doc1.`trackid` >= "TRAAAAK128F9318786") && (doc1.`trackid` <=
"TRAACER128F4290F96")) /* simple expression */ /* collections used:
doc1 : catalogue */
5 FilterNode 4693561782 - FILTER #11
43 IndexNode 42242056038 - FOR doc3 IN RepoEdges
/* edge index scan */
42 IndexNode 42242056038 - FOR doc4 IN
RepoNodes /* primary index scan */
41 IndexNode 380178504342 - FOR doc5 IN
RepoEdges /* edge index scan */
40 IndexNode 380178504342 - FOR doc6 IN
RepoNodes /* primary index scan */
39 IndexNode 3421606539078 - FOR doc7 IN
RepoEdges /* edge index scan */
38 IndexNode 3421606539078 - FOR doc8 IN
RepoNodes /* primary index scan */
37 IndexNode 143556923953556580 - FOR doc10
IN catalogue /* skiplist index scan */
36 IndexNode 1722683087442678800 - FOR
doc11 IN similarities /* edge index scan */
35 IndexNode 1722683087442678800 - FOR
doc12 IN clearance /* primary index scan */
Why it's impossible to do the same with a query like this:
FOR doc1 in catalogue
FOR doc2 in RepoNodes
FOR doc3 in RepoEdges
FOR doc4 in RepoNodes
FOR doc5 in RepoEdges
FOR doc6 in RepoNodes
FOR doc10 in catalogue
FOR doc11 in similarities
FOR doc12 in clearance
FILTER doc1.trackid== "TRAAAAK128F9318786" AND
doc1.trackid==doc2.mongodbsongs
AND doc3._from==doc2._id AND doc3._to ==doc4._id AND doc5._from==doc4._id
and doc6._id ==doc5._to
AND doc10.trackid== doc6.mongodbsongs
AND doc11._from==CONCAT("Tracks/",doc6.neo4jSong)
AND doc6.redisclearance== doc12._key
return {doc10,doc11,doc12}
It's the same query but with only one filter for the conditions, and this
causes a FULL COLLECTION SCAN for any of the collections.
why this happens?
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