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Querying with Regular Expressions

Explore how to apply regular expressions in MongoDB queries to match text patterns within documents. Understand key regex components like literals, metacharacters, and flags, and learn to combine regex with query operators. This lesson helps you build precise and flexible searches for effective data analysis.

What are regular expressions?

Regular expressions, also known as regex, are special text strings that define a search pattern. They can be used to search, match, and manipulate text within documents. MongoDB supports JavaScript-style regular expressions, making them both familiar and highly versatile.

Syntax:

Javascript (babel-node)
db.collection.find({ field: /pattern/ })

Here, field is the name of the field we want to search, and /pattern/ is the regex pattern we want to match. The pattern is enclosed between / slashes.

Components of a regular expression

Regex are not just random characters—they are a precise language for defining search patterns in text. At their core, regular expressions are made up of three main components:

  1. Literal characters

  2. Metacharacters

  3. Flags

Let's take a look at them in detail below: ...