Find documents with arrays not containing a document with a particular field value in MongoDB -

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i'm trying find documents not contain @ least 1 document specific field value. example here sample collection:

{  _id : 1,   docs : [         { foo : 1,           bar : 2},         { foo : 3,           bar : 3}          ] }, {  _id : 2,   docs : [         { foo : 2,           bar : 2},         { foo : 3,           bar : 3}          ] }

i want find every record there not document in docs block not contain @ least 1 record foo = 1. in example above, second document should returned.

i have tried following, tells me if there don't match (which returns document 1.

db.collection.find({"docs": { $not: {$elemmatch: {foo: 1 } } } })

update: query above work. many times happens, data wrong, not code.

i have looked @ $nin operator examples show when array contains list of primitive values, not additional document. when i've tried following, looks exact document rather foo field want.

db.collection.find({"docs": { $nin: {'foo':1 } } })

is there anyway accomplish basic operators?

using $nin work, have syntax wrong. should be:

db.collection.find({'docs.foo': {$nin: [1]}})

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