Migrating Database Oracle to Microsoft SQL Server

Migrating Database Oracle to Microsoft SQL Server

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In the current IT scenario, organizations are aware that Oracle is a very optimized database solution. But what swings opinion away from it is the high costs involved in running and maintaining the database. For example, for partitioning a table in Oracle, the user must pay for it. The same holds for using other advanced features like Database Encryption or Dynamic Data Masking. On the other hand, SQL Server offers these features out of the box in its Enterprise edition.

This cost factor is the key motive for an increasing number of organizations to optfor Oracle to SQL Server migration. This is also the reason why Microsoft helps its clients by providing cutting-edge tools specially designed for migration. This is the SQL Server Migration Assistant, better known as the SSMA tool, and is a built-in feature in almost all editions.

Benefits of Oracle to SQL Server Migration

Apart from the cost factor, there are several other benefits of Oracle to SQL Server migration

  • Oracle has significantly higher license charges than SQL Server. The costs in SQL Server are kept under control by compression of data, virtualizing servers, and database consolidation. SQL Server is also more user-friendly than the Oracle database and does not require the intervention of DBAs for running and maintenance, thereby further pruning recurring expenses.
  • High data safety and security are provided through a network of complex and encrypted algorithms by SQL Server. Sensitive and classified business data is protected by systems for permission management and strict tracking of user access.
  • There is a transparent and data compression facility in SQL Server which increases the performance of the database.
  • SQL Server can be easily installed with a Setup wizard that does not require a command-line configuration. Updates are automatically downloaded.
  • A key reason for Oracle to SQL Server migration is that SQL Server has many editions to match specific user profiles. Large organizations can use the Enterprise SQL edition while the Standard edition is perfect for mid and small-sized businesses. The free Express SQL Server edition has fewer features while the Developer SQL Server edition, almost similar to the Enterprise SQL edition is specifically meant for developers who want to test their applications on the SQL Server.
  • Restoring and recovering lost or damaged databases and getting the complete database back are among the top capabilities of the SQL Server. The main segment of the SQL Server database engine enables data storage and running queries of users through files, indexes, and transactions. The advantage of SQL Server over Oracle is that log records are entered on the disk before committing a transaction. In the event of a failure of the server hardware, a database engine instance, or an operating system, transaction logs are used by the instance after the restart to bring back the cut-off and incomplete transactions to the precise point of the crash or outage.
  • The maintenance and running costs of the SQL Server are quite low as compared to the Oracle database. The most affordable features include data mining and partitioning. The same goes for the tools for data maintenance and data storage.

These are some of the benefits why organizations today are increasingly opting for Oracle to SQL Server migration.

Preparatory Steps for Oracle to SQL Server Migration

Before the main process of data migration can be taken up, a few preparatory activities are required.

  • Install the SQL Server in the target database where the data will be migrated. It has to be ensured that proper connectivity is established between the Oracle source database and the Microsoft SQL Server target database.
  • SQL Server Migration Assistant (SSMA) and Oracle Client have to be installed in the target database.
  • Verify the connectivity to the port and any other firewall issues before launching SSMA and linking to the source database.
  • Map the Oracle schema to the target location where Oracle to SQL Server migration has to be carried out.
  • Convert and load all the Oracle database objects to the SQL Server. This can be done either by saving a script and applying it on the SQL Server or bringing all database objects in sync.

These are some of the essential activities required to set the stage for Oracle to SQL Server migration.It is also relevant for migrating an Oracle database to Azure SQL database and Azure Synapse Analytics.

Oracle to SQL Server Migration

Oracle to SQL Server migration can be done in two ways.

The first method is the easy and quick one-shot method where all systems are shut down and the full migration is completed in one go. Downtime is required as otherwise, all transactions that have been done since the last backup will not show in the target database. Before migration, run test executions so that migration goes off without a hitch. However, large and mid-sized enterprises might find it inconvenient to shut down systems for any length of time.

The second is the phased Oracle to SQL Server migration method that is done in two stages. First, the complete migration is done between the source and the target databases without shutting down the systems. Next, all incremental data and changes made after the last run are loaded to the target database at preset intervals.

Businesses can choose one of the two methods for Oracle to SQL Server migration in tune with their needs.