[Yandex Cloud documentation](../../index.md) > [Yandex Managed Service for YDB](../index.md) > [Tutorials](index.md) > Loading data from YDB to Yandex Object Storage using Yandex Data Transfer

# Loading data from Yandex Managed Service for YDB to Yandex Object Storage using Yandex Data Transfer

# Loading data from Yandex Managed Service for YDB to Yandex Object Storage using Yandex Data Transfer


You can migrate data from Managed Service for YDB to Object Storage using Data Transfer. Proceed as follows:

1. [Prepare your test data](#prepare-data).
1. [Prepare and activate the transfer](#prepare-transfer).
1. [Test the transfer](#verify-transfer).

If you no longer need the resources you created, [delete them](#clear-out).


## Required paid resources {#paid-resources}

* Managed Service for YDB database (see [Managed Service for YDB pricing](../pricing/index.md)). The cost depends on the deployment mode:

    * In serverless mode, you pay for data operations as well as the amount of stored data and backups.
    * In dedicated instance mode, you pay for the use of computing resources allocated to the database, storage size, and backups.

* Object Storage bucket: use of storage, data operations (see [Object Storage pricing](../../storage/pricing.md)).


## Getting started {#before-you-begin}


Set up your infrastructure:

{% list tabs group=instructions %}

- Manually {#manual}

    1. [Create a Managed Service for YDB database](../operations/manage-databases.md) of your preferred configuration.

    1. [Create an Object Storage bucket](../../storage/operations/buckets/create.md).

    
    1. [Create a service account](../../iam/operations/sa/create.md#create-sa) with the `storage.editor` and `ydb.editor` roles. The transfer will use it to access the database and bucket.


- Using Terraform {#tf}

    1. If you do not have Terraform yet, [install it](../../tutorials/infrastructure-management/terraform-quickstart.md#install-terraform).
    1. [Get the authentication credentials](../../tutorials/infrastructure-management/terraform-quickstart.md#get-credentials). You can add them to environment variables or specify them later in the provider configuration file.
    1. [Configure and initialize a provider](../../tutorials/infrastructure-management/terraform-quickstart.md#configure-provider). There is no need to create a provider configuration file manually, you can [download it](https://github.com/yandex-cloud-examples/yc-terraform-provider-settings/blob/main/provider.tf).
    1. Place the configuration file in a separate working directory and [specify the parameter values](../../tutorials/infrastructure-management/terraform-quickstart.md#configure-provider). If you did not add the authentication credentials to environment variables, specify them in the configuration file.

    1. Download the [ydb-to-object-storage.tf](https://github.com/yandex-cloud-examples/yc-data-transfer-from-ydb-to-object-storage/blob/main/ydb-to-object-storage.tf) configuration file to the same working directory.

        This file describes:

        * [Network](../../vpc/concepts/network.md#network).
        * [Subnet](../../vpc/concepts/network.md#subnet).
        * [Security group](../../vpc/concepts/security-groups.md).
        * Service account with the `storage.editor` and `ydb.editor` roles.
        * Object Storage target bucket.
        * Endpoints.
        * Transfer.

    1. In the `ydb-to-object-storage.tf` file, specify the following:
        * `folder_id`: [Folder ID](../../resource-manager/operations/folder/get-id.md).
        * `bucket_name`: Bucket name consistent with the [naming conventions](../../storage/concepts/bucket.md#naming).

    1. Validate your Terraform configuration files using this command:

        ```bash
        terraform validate
        ```

        Terraform will display any configuration errors detected in your files.

    1. Create the required infrastructure:

        1. Run this command to view the planned changes:
        
           ```bash
           terraform plan
           ```
        
           If you described the configuration correctly, the terminal will display a list of the resources to update and their parameters. This is a verification step that does not apply changes to your resources.
        
        1. If everything looks correct, apply the changes:
           1. Run this command:
        
              ```bash
              terraform apply
              ```
        
           1. Confirm updating the resources.
           1. Wait for the operation to complete.

        All the required resources will be created in the specified folder. You can check resource availability and their settings in the [management console](https://console.yandex.cloud).

{% endlist %}

## Prepare your test data {#prepare-data}

1. [Create](../operations/crud.md#web-sql) a table named `seasons` in the Managed Service for YDB database:

    ```sql
    CREATE TABLE seasons
    (
        series_id Uint64,
        season_id Uint64,
        title Utf8,
        first_aired Uint64,
        last_aired Uint64,
        PRIMARY KEY (series_id, season_id)
    );

    COMMIT;
     ```
1. Populate the table with data:

    ```sql
    REPLACE INTO seasons (series_id, season_id, title, first_aired, last_aired)
    VALUES
        (1, 1, "Season 1", CAST(Date("2006-02-03") AS Uint64), CAST(Date("2006-03-03") AS Uint64)),
        (1, 2, "Season 2", CAST(Date("2007-08-24") AS Uint64), CAST(Date("2007-09-28") AS Uint64)),
        (1, 3, "Season 3", CAST(Date("2008-11-21") AS Uint64), CAST(Date("2008-12-26") AS Uint64)),
        (1, 4, "Season 4", CAST(Date("2010-06-25") AS Uint64), CAST(Date("2010-07-30") AS Uint64)),
        (2, 1, "Season 1", CAST(Date("2014-04-06") AS Uint64), CAST(Date("2014-06-01") AS Uint64)),
        (2, 2, "Season 2", CAST(Date("2015-04-12") AS Uint64), CAST(Date("2015-06-14") AS Uint64)),
        (2, 3, "Season 3", CAST(Date("2016-04-24") AS Uint64), CAST(Date("2016-06-26") AS Uint64)),
        (2, 4, "Season 4", CAST(Date("2017-04-23") AS Uint64), CAST(Date("2017-06-25") AS Uint64)),
        (2, 5, "Season 5", CAST(Date("2018-03-25") AS Uint64), CAST(Date("2018-05-13") AS Uint64));

    COMMIT;
    ```

## Prepare and activate a transfer {#prepare-transfer}

{% list tabs group=instructions %}

- Manually {#manual}

    1. [Create a target endpoint](../../data-transfer/operations/endpoint/target/object-storage.md) of the `Object Storage` type with the following settings:

        * **Bucket**: `<name_of_previously_created_bucket>`.

        
        * **Service account**: `<name_of_previously_created_service_account>`.


        * **Serialization format**: `CSV`.
        * **Encoding format**: `UNCOMPRESSED`.
        * **Folder name**: `from_YDB`.

    1. [Create a source endpoint](../../data-transfer/operations/endpoint/source/ydb.md) of the `YDB` type with the following database connection settings:

        * **Database**: Select the YDB database from the list.

        
        * **Service account ID**: Select the service account you created earlier.


    1. [Create a transfer](../../data-transfer/operations/transfer.md#create) of the **Snapshot** type that will use the endpoints you created.

    1. [Activate the transfer](../../data-transfer/operations/transfer.md#activate) and wait for its status to change to **_Completed_**.

- Terraform {#tf}

    1. In the `ydb-to-object-storage.tf` file, specify the following variables:

        * `target_endpoint_id`: Target endpoint ID.
        * `source_endpoint_id`: Source endpoint ID.
        * `transfer_enabled`: Set to `1` to create a transfer.

    1. Validate your Terraform configuration files using this command:

        ```bash
        terraform validate
        ```

        Terraform will display any configuration errors detected in your files.

    1. Create the required infrastructure:

        1. Run this command to view the planned changes:
        
           ```bash
           terraform plan
           ```
        
           If you described the configuration correctly, the terminal will display a list of the resources to update and their parameters. This is a verification step that does not apply changes to your resources.
        
        1. If everything looks correct, apply the changes:
           1. Run this command:
        
              ```bash
              terraform apply
              ```
        
           1. Confirm updating the resources.
           1. Wait for the operation to complete.

    1. [Activate the transfer](../../data-transfer/operations/transfer.md#activate) and wait for its status to change to **_Completed_**.

{% endlist %}

## Test the transfer {#verify-transfer}

Make sure the data has been migrated from Managed Service for YDB to the Object Storage bucket:

1. In the [management console](https://console.yandex.cloud), select the folder containing your bucket.
1. Navigate to **Object Storage**.
1. Select the bucket from the list.
1. Navigate to the **Objects** tab.
1. Make sure the Object Storage bucket contains the `from_YDB` directory with the `<seasons.csv>` test data object.

## Delete the resources you created {#clear-out}

To minimize resource consumption, delete the resources you no longer need:

1. [Delete the transfer](../../data-transfer/operations/transfer.md#delete).
1. [Delete the endpoints](../../data-transfer/operations/endpoint/index.md#delete).
1. Delete the rest of the resources depending on how you created them:

   {% list tabs group=instructions %}

   - Manually {#manual}

       1. [Delete the Object Storage bucket](../../storage/operations/buckets/delete.md).
       1. [Delete the Managed Service for YDB database](../operations/manage-databases.md#delete-db).

       
       1. If you created any service account, [delete it](../../iam/operations/sa/delete.md).


   - Terraform {#tf}

       1. In the terminal window, go to the directory containing the infrastructure plan.
       
           {% note warning %}
       
           Make sure the directory has no Terraform manifests with the resources you want to keep. Terraform deletes all resources that were created using the manifests in the current directory.
       
           {% endnote %}
       
       1. Delete resources:
       
           1. Run this command:
       
               ```bash
               terraform destroy
               ```
       
           1. Confirm deleting the resources and wait for the operation to complete.
       
           All the resources described in the Terraform manifests will be deleted.

   {% endlist %}