Best way to implement case-insensitive queries in MongoDB

Question

What is the best way to implement case-insensitive queries in MongoDB?

For example, A database has a collection of contacts with a first name field. One document has 'Adam' in the first name field, another has 'adam'. What is the best way to query for documents with the first name = 'adam', regardless of the case?

Answer 1

Regex is your best bet:

db.collection.find({name: /^adam$/i})

If you're pre-3.2 then you'll need to use the $regex operator:

db.collection.find({name: { $regex: /^adam$/, $options: 'i'}})

Answer 2

db.contacts.find({firstName: /^adam$/i })