AWS DMS (database migration service) - Homogeneous vs. Heterogeneous database migration

If I have an MSSQL server on-premises and I want to migrate that in AWS cloud (as MSSQL server itself), this is called a homogeneous database migration.

If I have an MSSQL server on-premises and I want to transform and migrate that to a PostgreSQL database in AWS cloud, this is called a heterogeneous database migration. In this case the schema of the source and target database would be different (and also the datatypes, DB codes as the DB engines are different). So, you have to use a tool called SCT (schema conversion tool) to convert the source schema to the target schema (and also code transformation). After this, the DMS (database migration service) can be used to migrate the on-promises database into the AWS cloud (to RDS/EC2).

The major advantage of using DMS service is, the source database would be fully operational while migrating the database.

DMS can also move data between SQL, NoSQL and text-based targets.

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