![]() "award" : "National Medal of Technology",Īfter inserting the documents into the collection, we apply the find() method to retrieve the documents of the collection. The following documents are inserted into the student collection: > db.student.insertMany([Īfter inserting these documents into the collection, we apply $or operator and find only condition specified documents. Here, we apply the $or operation and show only those documents where age is greater than 25 and gender is Female. Now, See the execution of the above code in the MongoDB shell: The or operator retrieves all those documents that match at least one of the given expressions. We have got the result successfully as per the given condition. Read: Pros and cons of MongoDB MongoDB find multiple conditions match You can use the $or operator and retrieve the documents according to the condition. In MongoDB, we can apply the multiple conditions using the find() method and retrieve only those documents that match our documents. The find() method is used to select the documents from a collection and return a cursor to the selected documents. Here, the cursor indicates a pointer that points to a document. Let’s understand with the help of an example: when we use the find() method to return a pointer on the selected documents and returns one by one. ![]() ) Parametersīelow is the parameter description syntax of group by in MongoDB: The following documents are inserted into the person collections > db.person.Hadoop, Data Science, Statistics & others In this example, we apply multiple conditions to the documents using the find() method and return documents as per the condition. $group: This is defined as using accumulator and the expression we have retrieving the grouped data from the collection.The output of this aggregation is _id field which contains the group by key of distinct records. Group by is not order the result documents. _id: This field is mandatory while using aggregation with group operator.We can specify the id value with null value for calculating the accumulated value from the all input values. Expression: This is defined as expression which we have using with the group by in MongoDB.Accumulator: We are using the accumulator operator with group operator in MongoDB.Įxpression with group by is accepting the valid expression.Field: This is defined as field name which we are using with group by in MongoDB.īy using accumulator with the expression is accepting the valid expression.While using group by in MongoDB it is must to be use any one accumulator by using group by.We are using group method and aggregation operation to use group by in MongoDB. We are using below operator to group by multiple fields. $sum: This operator is used to return the sum of all the numeric fields using $group operator. ![]()
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