MongoDB – $lt Operator
MongoDB $lt operator or less than operator is one of the comparison operators. The $lt operator selects the documents with a value less than (<) the given value.
You can use this operator in methods like, find()
, update()
, etc. as per your requirements.
Syntax
{field: {$lt: value}}
MongoDB $lt Operator Example
In the following examples, we are working with:
Database: w3wiki
Collection: employee
Document: four documents that contain the details of the employees in the form of field-value pairs.
Example 1
In this example, we are selecting those documents where the value of the salary field is less than 35000.
Query:
find({salary: {lt:35000}}).pretty()
Output:
Example 2:
In this example, we are selecting only those documents where the age of the employee is less than 24.
Example 3:
In this example, we are selecting only those documents where the points array is less than the specified array.
Example 4:
In this example, we are updating the salary of those employees whose experience year is less than 2 years.
Key Takeaways About $lt Operator
- MongoDB $lt operator also known as less than operator is a comparison operator.
- It selects the documents where value of specific field is less than the given value.
- It can only compare similar data types. for example, string data type can not be compared with integer.
- It is useful for filtering wide range of documents.