node.js - MongoDB - Query array that contains nothing but specific values (javascript) -


im new mongodb , node. new forum please patient me.

when have documents these:

{_id: '1', name: 'doc1', values: [{name: 'val1', value: 'x'}]} {_id: '2', name: 'doc2', values: [{name: 'val1', value: 'x'}, {name: 'val2',  value: 'x'}]} {_id: '3', name: 'doc3', values: [{name: 'val1', value: 'x'}, {name: 'val2',  value: 'x'}, {name: 'val3', value: 'x'}]} {_id: '4', name: 'doc4', values: [{name: 'val1', value: 'x'}, {name: 'val3',  value: 'x'}]}

how search documents wich contain not (necessarily) given values like:

db.collection('col1').find(val1, val2);

and results:

doc1, doc2

the way, found accomplish following:

db.collection('col1').find({'values.name': {$nin: {['val3', everyotherpossiblevalue,...]}}})

but still search better (and - because everyotherpossiblevalue lot of values - shorter) query same thing

help appreciated :)

try this:

db.collection('col1').aggregate([{$unwind:'$values'},{$match:{$in:['val1','val2']}},{$group:{_id:"$name"}}])

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