MongoDB Comparison Query Operators

MongoDB comparison query operators filter documents by matching exact values or selecting value ranges across numeric, string, and date fields, helping retrieve relevant results efficiently.

• Exact match: Use $eq, $ne to match or exclude values.
• Multiple values: Use $in, $nin to match or exclude from a list of values.
• Range queries: Use $gt, $gte, $lt, $lte to filter ranges.
• Type support: Works with numbers, strings, and dates.
• Better filtering: Narrows results for faster, accurate queries.

MongoDB Comparison Operators

Examples using a sample "Students" collection in a database named "GeeksforGeeks".

• Database: GeeksforGeeks
• Collection: Students
• Document: Three documents that contain the details of the Students in the form of field-value pairs.

1. $nin operator

$nin matches none of the values specified in an array.

Example: Retrieving only those Student's documents whose name is not "Alen" or "Clevin".

db.Students.find({name: {$nin: ["Alen", "Clevin"]}})

Output:

2. $in operator

$in matches any of the values specified in an array.

Example: Retrieving only those students documents whose name is either "Alen" or "Clevin".

db.Students.find({name: {$in: ["Alen", "Clevin"]}})

Output:

3. $lt operator

$lt matches values of the fields that are less than a specified value.

Example: Retrieving those documents where the value of the salary field is less than 55000.

db.Students.find({salary: {$lt: 55000}})

Output:

4. $eq operator

$eq matches the values of the fields that are equal to a specified value.

Example: Retrieving those documents where the value of the branch field is equal to "CSE".

db.Students.find({branch: {$eq: "CSE"}})

Output:

5. $ne operator

$ne matches all values of the field that are not equal to a specified value.

Example: Retrieving those documents where the value of the branch field is not equal to CSE.

 db.Students.find({branch: {$ne: "CSE"}})

Output:

6. $gt operator

$gt matches values of the fields that are greater than a specified value.

Example: Retrieving those documents where the value of the salary field is greater than 5000.

db.Students.find({salary: {$gt: 5000}})

Output:

7. $gte operator

$gte matches values of the fields that are greater than or equal to the specified value.

Example: Retrieving those documents where the value of the joiningYear field is greater than equals to 2023.

db.Students.find({joiningYear: {$gte: 2023}})

Output:

8. $lte operator

$lte matches values of the fields that are less than or equal to the specified value.

Example: Retrieving those documents where the value of the joiningYear field is less than or equal to 2023.

db.Students.find({joiningYear: {$lte: 2023}})

Output: