Migrating data from REST to Snowflake using CData SSIS Components.

Snowflake is a leading cloud data warehouse and a popular backbone for enterprise BI, analytics, data management, and governance initiatives. Snowflake offers features such as data sharing, real-time data processing, and secure data storage which makes it a common choice for cloud data consolidation.

The CData SSIS Components enhance SQL Server Integration Services by enabling users to easily import and export data from various sources and destinations.

In this article, we explore the data type mapping considerations when exporting to Snowflake and walk through how to migrate REST data to Snowflake using the CData SSIS Components for REST and Snowflake.

Data Type Mapping

Special Considerations

• Casing: Snowflake enforces an exact case match by default for identifiers, so it is common to run into issues that can be attributed to mismatched casing. Set the IgnoreCase property to True in your CData SSIS Components for Snowflake connection to resolve these issues. This property directly maps to the QUOTED_IDENTIFIERS_IGNORE_CASE property in Snowflake and specifies whether Snowflake will treat identifiers as case-sensitive.

• Timestamps: Snowflake supports three timestamp types:

  • TIMESTAMP_NTZ: This timestamp stores UTC time with a specified precision. However, all operations are performed in the current session's time zone, controlled by the TIMEZONE session parameter.
  • TIMESTAMP_LTZ: This timestamp stores "wallclock" time with a specified precision. All operations are performed without taking any time zone into account.
  • TIMESTAMP_TZ: This timestamp stores UTC time together with an associated time zone offset. When a time zone isn't provided, the session time zone offset is used.

  By default the CData SSIS Components write timestamps to Snowflake as TIMESTAMP_NTZ unless manually configured.

Prerequisites

• Visual Studio 2022
• SQL Server Integration Services Projects extension for Visual Studio 2022
• CData SSIS Components for Snowflake
• CData SSIS Components for REST

Create the project and add components

1. Open Visual Studio and create a new Integration Services Project.
2. Add a new Data Flow Task to the Control Flow screen and open the Data Flow Task.
3. Add a CData REST Source control and a CData Snowflake Destination control to the data flow task.

Configure the REST source

Follow the steps below to specify properties required to connect to REST.

1. Double-click the CData REST Source to open the source component editor and add a new connection.
2. In the CData REST Connection Manager, configure the connection properties, then test and save the connection.

   See the Getting Started chapter in the data provider documentation to authenticate to your data source: The data provider models REST APIs as bidirectional database tables and XML/JSON files as read-only views (local files, files stored on popular cloud services, and FTP servers). The major authentication schemes are supported, including HTTP Basic, Digest, NTLM, OAuth, and FTP. See the Getting Started chapter in the data provider documentation for authentication guides.

   After setting the URI and providing any authentication values, set Format to "XML" or "JSON" and set DataModel to more closely match the data representation to the structure of your data.

   The DataModel property is the controlling property over how your data is represented into tables and toggles the following basic configurations.

   • Document (default): Model a top-level, document view of your REST data. The data provider returns nested elements as aggregates of data.
   • FlattenedDocuments: Implicitly join nested documents and their parents into a single table.
   • Relational: Return individual, related tables from hierarchical data. The tables contain a primary key and a foreign key that links to the parent document.

   See the Modeling REST Data chapter for more information on configuring the relational representation. You will also find the sample data used in the following examples. The data includes entries for people, the cars they own, and various maintenance services performed on those cars.

   
3. After saving the connection, select "Table or view" and select the table or view to export into Snowflake, then close the CData REST Source Editor.

Configure the Snowflake destination

With the REST Source configured, we can configure the Snowflake connection and map the columns.

1. Double-click the CData Snowflake Destination to open the destination component editor and add a new connection.
2. In the CData Snowflake Connection Manager, configure the connection properties, then test and save the connection.
   • The component supports Snowflake user authentication, federated authentication, and SSL client authentication. To authenticate, set User and Password, and select the authentication method in the AuthScheme property. Starting with accounts created using Snowflake’s bundle 2024_08 (October 2024), password-based authentication is no longer supported due to security concerns. Instead, use alternative authentication methods such as OAuth or Private Key authentication.

   Other helpful connection properties

   • QueryPassthrough: When this is set to True, queries are passed through directly to Snowflake.
   • ConvertDateTimetoGMT: When this is set to True, the components will convert date-time values to GMT, instead of the local time of the machine.
   • IgnoreCase: A session parameter that specifies whether Snowflake will treat identifiers as case sensitive. Default: false(case is sensitive).
   • BindingType: There are two kinds of binding types: DEFAULT and TEXT. DEFAULT uses the binding type DATE for the Date type, TIME for the Time type, and TIMESTAMP_* for the Timestamp_* type. TEST uses the binding type TEXT for Date, Time, and Timestamp_* types.
   
3. After saving the connection, select a table in the Use a Table menu and in the Action menu, select Insert.
4. On the Column Mappings tab, configure the mappings from the input columns to the destination columns.

Run the project

You can now run the project. After the SSIS Task has finished executing, data from your SQL table will be exported to the chosen table.