# mongoc_client_encryption_encrypt_opts_set_keyid()

## Synopsis

    void
    mongoc_client_encryption_encrypt_opts_set_keyid (
       mongoc_client_encryption_encrypt_opts_t *opts, const bson_value_t *keyid);

Identifies the data key to use for encryption. This option is mutually exclusive with mongoc_client_encryption_encrypt_opts_set_keyaltname().

## Parameters

- `opts`: A mongoc_client_encryption_encrypt_opts_t

- `keyid`: A UUID (BSON binary with subtype 4) corresponding to the `_id` of the data key.

See also

mongoc_client_encryption_encrypt_opts_set_keyaltname()