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MongoDB Query Operators

There are many query operators that can be used to compare and reference document fields.

Comparison

The following operators can be used in queries to compare values:

• $eq: Values are equal
• $ne: Values are not equal
• $gt: Value is greater than another value
• $gte: Value is greater than or equal to another value
• $lt: Value is less than another value
• $lte: Value is less than or equal to another value
• $in: Value is matched within an array

Logical

The following operators can logically compare multiple queries.

• $and: Returns documents where both queries match
• $or: Returns documents where either query matches
• $nor: Returns documents where both queries fail to match
• $not: Returns documents where the query does not match

Evaluation

The following operators assist in evaluating documents.

• $regex: Allows the use of regular expressions when evaluating field values
• $text: Performs a text search
• $where: Uses a JavaScript expression to match documents

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