distinct

The distinct command finds the distinct values for a specified field across a single collection. The command returns a document that contains an array of the distinct values as well as the query plan and status. The command takes the following prototype form:

{ distinct: collection, key: <field>, query: <query> }

The command fields are as follows:

Consider the following examples of the distinct command:

• Return an array of the distinct values of the field ord_dt from all documents in the orders collection:

  db.runCommand ( { distinct: 'orders', key: 'ord_dt' } )
  

• Return an array of the distinct values of the field sku in the subdocument item from all documents in the orders collection:

  db.runCommand ( { distinct: 'orders', key: 'item.sku' } )
  

• Return an array of the distinct values of the field ord_dt from the documents in the orders collection where the price is greater than 10:

  db.runCommand ( { distinct: 'orders',
                    key: 'ord_dt',
                    query: { price: { $gt: 10 } }
                  } )