To find on the basis of true or false values, use $exists in find(). You would also need dot notation for the same task.
Let us first create a collection with documents −
> db.demo367.insertOne( ... { "Id" : "102", ... "details" : [ { "Name" : "David"}, ... { "Age" : 23, "CountryName" : "UK"} ], ... "isMarried" : false } ... ); { "acknowledged" : true, "insertedId" : ObjectId("5e57e0b62ae06a1609a00ae8") } > db.demo367.insertOne( ... { "Id" : "101", ... "details" : [ { "Name" : "Chris", "Subject" : [ "MySQL" ] }, ... { "Age" : 21, "CountryName" : "US"} ], ... "isMarried" : true } ... ); { "acknowledged" : true, "insertedId" : ObjectId("5e57e0be2ae06a1609a00ae9") }
Display all documents from a collection with the help of find() method −
> db.demo367.find();
This will produce the following output −
{ "_id" : ObjectId("5e57e0b62ae06a1609a00ae8"), "Id" : "102", "details" : [ { "Name" : "David" }, { "Age" : 23, "CountryName" : "UK" } ], "isMarried" : false } { "_id" : ObjectId("5e57e0be2ae06a1609a00ae9"), "Id" : "101", "details" : [ { "Name" : "Chris", "Subject" : [ "MySQL" ] }, { "Age" : 21, "CountryName" : "US" } ], "isMarried" : true }
Following is the query to find on the basis of true false values by checking with $exists −
> db.demo367.find({"details.Subject": { $exists: false}});
This will produce the following output −
{ "_id" : ObjectId("5e57e0b62ae06a1609a00ae8"), "Id" : "102", "details" : [ { "Name" : "David" }, { "Age" : 23, "CountryName" : "UK" } ], "isMarried" : false }