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To create a unique index, use the db.collection.createIndex() method with the unique option set to true. db. collection. createIndex ( <key and index type specification>, { unique: true } ) Unique Index on a Single Field. For example, to create a unique index on the user_id field of the members collection, use the following operation in mongosh:
28 Οκτ 2024 · How to Create Unique Index MongoDB? In MongoDB, unique indexes can be created at the collection level using the createIndex() method or by specifying the unique option when defining the index in a collection's schema. Example 1: Unique Index on a Single Field // Create a unique index on the "username" field of the "users" collection
1 Φεβ 2024 · This cheat sheet covered a range of MongoDB Shell commands from basic to more advanced ones. These commands form the backbone of data operations, administration, and performance optimizations in MongoDB.
16 Νοε 2021 · db.users.createIndex( { email: 1 }, { unique: true } ) This will create the empty collection (with name as users) as well as the unique index on the email field. And, you can verify the index creation with this command: db.users.getIndexes() Also, refer MongoDB Manual about Indexes.
2 Φεβ 2024 · Creating a Unique Index. db.collection.createIndex({"email": 1}, {unique: true}); The above command creates a unique index on the email field in the collection. This will prevent two documents from having the same email. Adding a Unique Constraint to an Existing Collection.
31 Ιαν 2022 · First steps in the MongoDB World? This cheat sheet is filled with some handy tips, commands, and quick references to get you connected and CRUD'ing in no time!
Steps. Learn More. To convert a non-unique index to a unique index, use the collMod command. The collMod command provides options to verify that your indexed field contains unique values before you complete the conversion. Before you Begin. 1. Populate sample data. apples. 2. Create a single field index. type.
