Amazon Web Service Database Migration Service is a cloud-based service that facilitates migration between on-premises databases to the cloud or from one cloud provider to another.
The advantage of AWS DMS is that during migration, the source database remains fully functional and hence there is no need for downtime. Data can be continually replicated with high availability and several databases consolidated into a petabyte-sized one through data streaming to Amazon S3 or Amazon Redshift.
There are two forms of database migration with AWS DMS.
Homogeneous database migration
This type of database migration is when the engines of the source and the target databases as well as the data types, data codes, and the schema structures are similar. Examples are Microsoft SQL Server to Amazon RDS for SQL Server, MySQL to Amazon Aurora, Oracle to Amazon RDS for Oracle, or MySQL to Amazon RDS for MySQL. Because of the similarities, database migration with AWS DMSis a one-step process. The source database may be an Amazon RDS database or located outside the AWS while the target database may be in the Amazon EC2 instance or Amazon RDS.
Heterogenous database migration
Migration here with AWS DMS is when the database engines, data types, data codes, and the schema structures of the source and the target databases are different. Examples of heterogeneous migration include Oracle to Amazon Aurora, Microsoft SQL Server to MySQL migrations, or Oracle to PostgreSQL. Hence for migration, the AWS Schema Conversion Tool is first used to convert the data codes and the schema structures of the source database to match that of the target database before migration can be initiated.
These are the forms of migration with AWS database migration service
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