Couchbase N1QL query really slow - couchbase

Question

I'm working on a project where we use Couchbase 4.1 and we are trying to use N1QL to query for documents. Problem is that it seems very slow even though I have created indexees. The query takes around ~2 seconds with ~11000 documents.
The query:
SELECT name, displayName, imageId, childCategories FROM `bd-couchbase` WHERE assortment = 'CategoryAssortmentOne' AND categoryPath = 'category-displayname/subcategory-displayName' AND displayName IS NOT MISSING
My document is looking like this:
{
"parentName": "8442",
"categoryPath": "category-displayname/subcategory-displayName",
"lastUpdated": "2016-05-31T11:02:03.5129252+02:00",
"childCategories": [
{
"name": "0041",
"displayName": "Category 1",
"imageId": "0041"
},
{
"name": "0042",
"displayName": "Category 2",
"imageId": "0042"
},
{
"name": "0043",
"displayName": "Category 3",
"imageId": "0043"
},
{
"name": "0044",
"displayName": "Category 4",
"imageId": "0044"
},
{
"name": "0045",
"displayName": "Category 5",
"imageId": "0045"
},
{
"name": "0046",
"displayName": "Category 6",
"imageId": "0046"
}
],
"assortment": "CategoryAssortmentOne",
"name": "0040",
"displayName": "MyCategory",
"imageId": "0040"
}
I have the following index:
CREATE INDEX `category_idx` ON `bd-couchbase`((meta().`id`),`name`,`displayName`,`imageId`,`categoryPath`,`childCategories`,`assortment`) USING GSI;
When I execute the explain I can see it uses the #primary index and then doing a fetch (which I guess is the slow part of the query). But when I have created my index is not then supposed to use that?
The result of my explain:
{
"requestID": "da1946f3-5cc8-4d1e-a05b-06789aa6be92",
"signature": "json",
"results": [
{
"#operator": "Sequence",
"~children": [
{
"#operator": "PrimaryScan",
"index": "#primary",
"keyspace": "my-couchbase",
"namespace": "default",
"using": "gsi"
},
{
"#operator": "Parallel",
"~child": {
"#operator": "Sequence",
"~children": [
{
"#operator": "Fetch",
"keyspace": "my-couchbase",
"namespace": "default"
},
{
"#operator": "Filter",
"condition": "((((`my-couchbase`.`assortment`) =
\"CategoryAssortmentOne\") and ((`my-couchbase`.`categoryPath`) = \"category-displayname/subcategory-displayName\")) and ((`my-couchbase`.`displayName`) is not missing))"
},
{
"#operator": "InitialProject",
"result_terms": [
{
"expr": "(`my-couchbase`.`name`)"
},
{
"expr": "(`my-couchbase`.`displayName`)"
},
{
"expr": "(`my-couchbase`.`imageId`)"
},
{
"expr": "(`my-couchbase`.`childCategorie
s`)"
}
]
},
{
"#operator": "FinalProject"
}
]
}
}
]
}
],
"status": "success",
"metrics": {
"elapsedTime": "13.6696ms",
"executionTime": "13.6696ms",
"resultCount": 1,
"resultSize": 2089
}
}
Any suggestions?
Thanks in advance.

Answer 1

the query service didn't seem to be able to match your index with the query. any particular reason you included the meta.id in the index?
try redefining the index to cover only the fields used in your WHERE clause: assortment, categoryPath and displayName, and see if it gets mentioned in the EXPLAIN after that.
CREATE INDEX category_idx ON `bd-couchbase`(assortment, categoryPath, displayName, imageId, childCategories, name);