To pull values, use $pull and set multi: true. Let us first create a collection with documents −
> db.demo392.insertOne( ... { ... Name: 'Chris', ... details: [ ... { ... _id: '101' ... ... }, ... { ... _id: '102' ... } ... ] ... } ... ); { "acknowledged" : true, "insertedId" : ObjectId("5e5d2b3322064be7ab44e802") } > > db.demo392.insertOne( ... { ... Name: 'Chris', ... details: [ ... { ... _id: '104' ... ... }, ... { ... _id: '101' ... } ... ] ... } ... ); { "acknowledged" : true, "insertedId" : ObjectId("5e5d2b3422064be7ab44e803") }
Display all documents from a collection with the help of find() method −
> db.demo392.find();
This will produce the following output −
{ "_id" : ObjectId("5e5d2b3322064be7ab44e802"), "Name" : "Chris", "details" : [ { "_id" : "101" }, { "_id" : "102" } ] } { "_id" : ObjectId("5e5d2b3422064be7ab44e803"), "Name" : "Chris", "details" : [ { "_id" : "104" }, { "_id" : "101" } ] }
Following is the query to $pull from array −
> db.demo392.update( ... { }, ... { $pull: { details: { _id: '101' } } }, ... { multi: true } ... ) WriteResult({ "nMatched" : 2, "nUpserted" : 0, "nModified" : 2 })
Display all documents from a collection with the help of find() method −
> db.demo392.find();
This will produce the following output −
{ "_id" : ObjectId("5e5d2b3322064be7ab44e802"), "Name" : "Chris", "details" : [ { "_id" : "102" } ] } { "_id" : ObjectId("5e5d2b3422064be7ab44e803"), "Name" : "Chris", "details" : [ { "_id" : "104" } ] }