How do I find a specific field in MongoDB?

How do I find a specific field in MongoDB?

You can select a single field in MongoDB using the following syntax: db. yourCollectionName. find({“yourFieldName”:yourValue},{“yourSingleFieldName”:1,_id:0});

How do I project a field in MongoDB?

Starting in MongoDB 4.4, you can also specify embedded fields using the nested form, e.g. { item: 1, status: 1, size: { uom: 1 } } ….Return Specific Fields in Embedded Documents

1. The _id field (returned by default),
2. The item field,
3. The status field,
4. The uom field in the size document.

How do I filter a field in MongoDB?

Set Query Filter

1. In the Filter field, enter a filter document. You can use all of the MongoDB query operators except the $text and $expr operators. Example. The following filter only returns documents which have a Country value of Brazil :
2. Click Find to run the query and view the updated results. click to enlarge.

How do I add a field to a collection in MongoDB?

Same as the updating existing collection field, $set will add a new fields if the specified field does not exist. EDIT: In the above example last 2 fields false, true specifies the upsert and multi flags. Upsert: If set to true, creates a new document when no document matches the query criteria.

How do I group multiple fields in MongoDB?

The best way of grouping the Multiple fields present inside the documents of MongoDB is made by the $group operator. This operator helps you in executing the various other aggregation functions as well on the grouped data.

How do I query an array field in MongoDB?

To query if the array field contains at least one element with the specified value, use the filter { : } where is the element value. To specify conditions on the elements in the array field, use query operators in the query filter document: { : { : , } }

What does find return in MongoDB?

find() returns the cursor of Result Set of a query by which you can iterate over the result set or print all documents.

How do I add a field to an existing document in MongoDB using a compass?

Procedure

1. Click the Add Data dropdown and select Insert Document.
2. Select the appropriate view based on how you would like to insert documents. Click the { } brackets for JSON view. This is the default view. Click the list icon for Field-by-Field mode. JSON View Field-by-Field Editor.

What is field in MongoDB?

The _id Field In MongoDB, each document stored in a collection requires a unique _id field that acts as a primary key. If an inserted document omits the _id field, the MongoDB driver automatically generates an ObjectId for the _id field.

How do I query an array of objects in MongoDB?

To search the array of object in MongoDB, you can use $elemMatch operator. This operator allows us to search for more than one component from an array object. Here is the query to search in an array of objects in MongoDB.

How do I display multiple fields in MongoDB?

How to query MongoDB?

Prerequisites. A server with a regular,non-root user with sudo privileges and a firewall configured with UFW.

Preparing the Sample Database. To explain how to create queries in MongoDB — including how to filter documents with multiple fields,nested documents,and arrays — this

Querying Individual Fields.

Using Multiple Conditions.

What is distinct in MongoDB?

MongoDB distinct method returns a set of discrete values for the field specified as the input argument. Mongo distinct method returns an array of discrete values. MongoDB distinct. field: A string type for which the discrete values are to be returned. query: Specifies the document from which discrete values are to be retrieved.

What is the query language for MongoDB?

MongoDB uses JavaScript as the main query language. If you install MongoDB you will be able to see the JavaScript language interpreter is installed by default. In terms of query language you can choose from a variety of scripting languages for MongoDB like python, PHP or perl.

What is MongoDB documentation?

A record in MongoDB is a document, which is a data structure composed of field and value pairs. The values of the fields may include other documents, arrays, and arrays of documents (a group of documents is a collection, such as a table in RDBMS).