righthh.blogg.se - Mongodb compass filter by id

Suppose there are two or more documents in the collections having the same value for the particular field.bLet see the situation with the help of the data present in the collection similar to the one given below: As the “name” is also a field on which each document can be filtered, so the document having the “name” as “sunita” is found and all its details are displayed to the user on the console.As we can see in the above example, the user can also put the parameter of find function of the other fields of the document.Using the find() function by passing the parameters of the fields other than the unique objectId. We can provide the ObjectId as a parameter of the find() function in MongoDB and its respective document is displayed on the console to the user.ObjectId is the unique id that is automatically allocated when a new document is inserted into the collection.

In the above example, the document is found on the basis of the ObjectId of the document.

When the user calls findById(_id) in Mongoose, it automatically calls findOne().

As the name suggests, find by id is used to retrieve the details of the document matching the particular ‘id’ provided by the user where ‘id’ is the automatically generated ‘id’ when a document is created in the database.

It returns the cursor to the documents which match the query criteria. This parameter can be omitted in order to return all the fields in the matching documents. It specifies the field which will return matching the query filter.

projection: It is an optional parameter.

This parameter can be omitted in order to return all the documents in a collection. It specifies the selection filter using the operators of the query.