List all values of a certain field in MongoDB?

To get the list of all values of certain fields in MongoDB, you can use distinct(). The syntax is as follows −

db.yourCollectionName.distinct( "yourFieldName");

To understand the above syntax, let us create a collection with the document. The query to create a collection with a document is as follows −

> db.listAllValuesOfCeratinFieldsDemo.insertOne({"ListOfValues":[10,20,30]});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5c8fc89ed3c9d04998abf011")
}
> db.listAllValuesOfCeratinFieldsDemo.insertOne({"ListOfValues":[40,50,60]});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5c8fc8abd3c9d04998abf012")
}
> db.listAllValuesOfCeratinFieldsDemo.insertOne({"ListOfValues":[10,20,30]});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5c8fc8d7d3c9d04998abf013")
}
> db.listAllValuesOfCeratinFieldsDemo.insertOne({"ListOfValues":[40,50,70]});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5c8fc8e2d3c9d04998abf014")
}

Display all documents from a collection with the help of find() method. The query is as follows −

> db.listAllValuesOfCeratinFieldsDemo.find().pretty();

The following is the output −

{
   "_id" : ObjectId("5c8fc89ed3c9d04998abf011"),
   "ListOfValues" : [
      10,
      20,
      30
   ]
}
{
   "_id" : ObjectId("5c8fc8abd3c9d04998abf012"),
   "ListOfValues" : [
      40,
      50,
      60
   ]
}
{
   "_id" : ObjectId("5c8fc8d7d3c9d04998abf013"),
   "ListOfValues" : [
      10,
      20,
      30
   ]
}
{
   "_id" : ObjectId("5c8fc8e2d3c9d04998abf014"),
   "ListOfValues" : [
      40,
      50,
      70
   ]
}

Here is the query to get the list all values of a certain field in MongoDB. We are displaying the record of the field ‘ListOfValues’ −

> db.listAllValuesOfCeratinFieldsDemo.distinct( "ListOfValues");

The following is the output −

[ 10, 20, 30, 40, 50, 60, 70 ]