> For the complete MongoDB documentation index, see www.mongodb.com/docs/llms.txt

# Enabling Queryable Encryption when Creating Collections

## Overview

Enable Queryable Encryption at collection creation. You can't encrypt fields on documents that are already in a collection.

**Important:**

Explicitly create your collection, rather than creating it implicitly with an insert operation. When you create a collection using `createCollection()`, MongoDB creates an index on the encrypted fields. Without this index, queries on encrypted fields may run slowly.

## Enable Queryable Encryption on a Collection

You can enable Queryable Encryption on fields in one of two ways. The following examples use Node.js to enable Queryable Encryption:

- Pass the encryption schema, represented by the `encryptedFieldsObject` constant, to the client that the application uses to create the collection:

  ```javascript
  const client = new MongoClient(uri, {
     autoEncryption: {
        keyVaultNameSpace: "<your keyvault namespace>",
        kmsProviders: "<your kms provider>",
        extraOptions: {
           cryptSharedLibPath: "<path to Automatic Encryption Shared Library>"
        },
        encryptedFieldsMap: {
           "<databaseName.collectionName>": { encryptedFieldsObject }
        }
     }

     ...

     await client.db("<database name>").createEncryptedCollection("<collection name>");
  }
  ```

  For more information on `autoEncryption` configuration options, see the section on [MongoClient Options for Queryable Encryption.](https://www.mongodb.com/docs/manual/core/queryable-encryption/reference/qe-options-clients.md#std-label-qe-reference-mongo-client)

- Pass the encryption schema `encryptedFieldsObject` to `createEncryptedCollection()`:

  ```javascript
  await encryptedDB.createEncryptedCollection("<collection name>", {
     encryptedFields: encryptedFieldsObject
  });
  ```

  **Tip:**

  Specify the `encryptedFieldsObject` when you create the collection, and also when you create a client to access the collection. For more information about the security considerations of not defining the `encryptedFieldsObject`, see [Security Considerations.](https://www.mongodb.com/docs/manual/core/queryable-encryption/about-qe-csfle.md#std-label-qe-csfle-security-considerations)