New – A Fully Managed Schema Conversion in AWS Database Migration Service

Since we launched AWS Database Migration Service (AWS DMS) in 2016, customers have securely migrated more than 800,000 databases to AWS with minimal downtime. AWS DMS supports migration between 20+ database and analytics engines, such as Oracle to Amazon Aurora MySQL, MySQL to Amazon Relational Database (Amazon RDS) MySQL, Microsoft SQL Server to Amazon Aurora PostgreSQL, MongoDB to Amazon DocumentDB, Oracle to Amazon Redshift, and to and from Amazon Simple Storage Service (Amazon S3).

Specifically, the AWS Schema Conversion Tool (AWS SCT) makes heterogeneous database and data warehouse migrations predictable and can automatically convert the source schema and a majority of the database code objects, including views, stored procedures, and functions, to a format compatible with the target engine. For example, it supports the conversion of Oracle PL/SQL and SQL Server T-SQL code to equivalent code in the Amazon Aurora MySQL dialect of SQL or the equivalent PL/pgSQL code in PostgreSQL. You can download the AWS SCT for your platform, including Windows or Linux (Fedora and Ubuntu).

Today we announce fully managed AWS DMS Schema Conversion, which streamlines database migrations by making schema assessment and conversion available inside AWS DMS. With DMS Schema Conversion, you can now plan, assess, convert and migrate under one central DMS service. You can access features of DMS Schema Conversion in the AWS Management Console without downloading and executing AWS SCT.

AWS DMS Schema Conversion automatically converts your source database schemas, and a majority of the database code objects to a format compatible with the target database. This includes tables, views, stored procedures, functions, data types, synonyms, and so on, similar to AWS SCT. Any objects that cannot be automatically converted are clearly marked as action items with prescriptive instructions on how to migrate to AWS manually.

In this launch, DMS Schema Conversion supports the following databases as sources for migration projects:

• Microsoft SQL Server version 2008 R2 and higher
• Oracle version 10.2 and later, 11g and up to 12.2, 18c, and 19c

DMS Schema Conversion supports the following databases as targets for migration projects:

• Amazon RDS for MySQL version 8.x
• Amazon RDS for PostgreSQL version 14.x

Setting Up AWS DMS Schema Conversion
To get started with DMS Schema Conversion, and if it is your first time using AWS DMS, complete the setup tasks to create a virtual private cloud (VPC) using the Amazon VPC service, source, and target database. To learn more, see Prerequisites for AWS Database Migration Service in the AWS documentation.

In the AWS DMS console, you can see new menus to set up Instance profiles, add Data providers, and create Migration projects.

Before you create your migration project, set up an instance profile by choosing Instance profiles in the left pane. An instance profile specifies network and security settings for your DMS Schema Conversion instances. You can create multiple instance profiles and select an instance profile to use for each migration project.

Choose Create instance profile and specify your default VPC or a new VPC, Amazon Simple Storage Service (Amazon S3) bucket to store your schema conversion metadata, and additional settings such as AWS Key Management Service (AWS KMS) keys.

You can create the simplest network configuration with a single VPC configuration. If your source or target data providers are in different VPCs, you can create your instance profile in one of the VPCs, and then link these two VPCs by using VPC peering.

Next, you can add data providers that store the data store type and location information about your source and target databases by choosing Data providers in the left pane. For each database, you can create a single data provider and use it in multiple migration projects.

Your data provider can be a fully managed Amazon RDS instance or a self-managed engine running either on-premises or on an Amazon Elastic Compute Cloud (Amazon EC2) instance.

Choose Create data provider to create a new data provider either a source or target. You can set the type of the RDS instances or database location manually, such as database engine, domain name or IP address, port number, database name, and so on, for your data provider. Here, I have selected an Enter manually.

After you create a data provider, make sure that you add database connection credentials in AWS Secrets Manager. DMS Schema Conversion uses this information to connect to a database.

Converting your database schema with AWS DMS Schema Conversion
Now, you can create a migration project for DMS Schema Conversion by choosing Migration projects in the left pane. A migration project describes your source and target data providers, your instance profile, and migration rules. You can also create multiple migration projects for different source and target data providers.

Choose Create migration project and select your instance profile and source and target data providers for DMS Schema Conversion.

After creating your migration project, you can use the project to create assessment reports and convert your database schema. Choose your migration project from the list, then choose the Schema conversion tab and click Launch schema conversion.

Migration projects in DMS Schema Conversion are always serverless. This means that AWS DMS automatically provisions the cloud resources for your migration projects, so you don’t need to manage schema conversion instances.

Of course, the first launch of DMS Schema Conversion requires starting a schema conversion instance, which can take up to 10–15 minutes. This process also reads the metadata from the source and target databases. After a successful first launch, you can access DMS Schema Conversion faster.

An important part of DMS Schema Conversion is that it generates a database migration assessment report that summarizes all of the schema conversion tasks. It also details the action items for schema that cannot be converted to the DB engine of your target database instance. You can view the report in the AWS DMS console or export it as a comma-separated value (.csv) file.

To create your assessment report, choose the source database schema or schema items that you want to assess. After you select the checkboxes, choose Assess in the Actions menu in the source database pane. This report will be archived with CSV and PDF files in your S3 bucket. To change the S3 bucket, edit the schema conversion settings in your instance profile.

Then, you can apply the converted code to your target database or save it as a SQL script. To apply converted code, choose Convert in the pane of Source data provider and then Apply changes in the pane of Target data provider.

Once the schema has been converted successfully, you can move on to the database migration phase using AWS DMS. To learn more, see Getting started with AWS Database Migration Service in the AWS documentation.

Now Available
AWS DMS Schema Conversion is now available in the US East (Ohio), US East (N. Virginia), US West (Oregon), Asia Pacific (Singapore), Asia Pacific (Sydney), Asia Pacific (Tokyo), Europe (Frankfurt), Europe (Ireland), and Europe (Stockholm) Regions, and you can start using it today.

To learn more, see the AWS DMS Schema Conversion User Guide, give it a try, and please send feedback to AWS re:Post for AWS DMS or through your usual AWS support contacts.

– Channy