In this post, we will go into the various aspects of migrating databases from Oracle to the Microsoft SQL Server. The key takeaways will be the benefits that come with this migration and the process of doing so.
So, let us get started.
The modern business environment is typically data-driven with massive volumes of data being routinely processed. Hence, among the operational goals of any organization is to first, have a cost-effective infrastructure in place and second, have an IT structure that is technologically advanced with cutting-edge features. Moreover, stringent data security norms should also be in place.
One of the ways to ensure that all these capabilities can be had at the operational level is to migrate databases from Oracle to SQL Server.
Benefits of Moving Databases from Oracle to SQL Server
As stated before, the value of moving databases from Oracle to SQL Server should be evaluated from two perspectives. One is the cost-effectiveness and affordability and the other is the functional capabilities.
Affordability
Costs are kept under control in the SQL Server in several ways.
- SQL Server offers data compression facilities to the extent of 10x. This means that large volumes of data can be stored in limited spaces, thereby significantly reducing storage costs. Along with data consolidation and visualization of servers, this data compression facility is a critical component of the SQL Server.
- Oracle charges fixed licensing costs with flat fees, regardless of the type of features and storage volumes required by organizations. On the other hand, the SQL Server has a multi-layer system with several versions tailor-made for the size of the business. Let us check them out.
The most expensive license fee is for the Enterprise edition with large storage capabilities and high computing power, ideal for large established businesses. The next is the Standard edition with lower license fees and fewer features and storage. Finally, there is the free Express edition, ideal for individuals and startups. Businesses can start with their basic requirements and move up as their business grows. This tiering is a huge cost saver for users and is a very critical motive for migrating databases from Oracle to SQL Server.
Cutting-edge Capabilities
The SQL Server offers many advanced features that make it a cut above the Oracle. Let us examine each of them.
- The database engine of the SQL Server stores data and runs queries through indexes, files, and transactions. Hence it is ideally placed to recover and restore a database if a system crash occurs. Before finalizing any transaction in the SQL Server, log records are written on a disk. When an outage happens, these transaction logs help to carry on with the work without a break or downtime.
When the status quo is restored, the logs are used to restore the transactions from where the break occurred. Hence, there is no loss or performance degradation for business in the event of an outage.
- The installation of traditional databases such as Oracle is often quite complex and other drivers and applications must be downloaded first. On the other hand, for installing the SQL Server, a Setup Wizard is sufficient without the need for any command-line configuration. Once the setup is completed, all updates and upgrades are automatically downloaded.
- One aspect that sets SQL Server a notch above the Oracle database is data safety and security, Data in SQL Server is encrypted and protected through complex algorithms, and access to the data is strictly controlled. Optimized access management programs are in place that firewall all classified and confidential data.
Because of these reasons, it is wise to migrate databases from Oracle to SQL Server.
Migrating Databases From Oracle to SQL Server
The overall process of migrating databases from Oracle to SQL Server consists of two parts, laying the groundwork and the migration proper.
Initial work for database migration
- Install SQL Server in the database where data is to be moved. Establish a link between the Oracle database and the target database. Also, install Oracle Client and SSMA (SQL Server Migration Assistant) in the target database. Ensure that there are no firewall issues before launching SSMA.
- Map the schema to the target database where the data will be migrated.
- Load all Oracle database objects to the SQL Server either by saving a script and applying it to the SQL Server or syncing all database objects.
- Before starting the process of migrating the database from Oracle to SQL Server, check the key metrics and peak load frequencies. Next, implement SQL Server Distributed Replay that reruns the quantum of work expected on the load harness.
After these steps, the final stage of migrating a database from Oracle to SQL Server can be initiated.
The Migration Process
Database migration from Oracle to SQL Server can be carried out in one of two ways.
- The whole migration process is carried out in one run after shutting down all systems. This process is relatively easy and less complex than the other. The reason why all systems must be shut down is because any incremental data that is generated after the start of the migration will not be reflected in the target database.
This method though is not suitable for very large organizations as shutting down systems even for a limited time will adversely affect operational efficiencies.
- This process of Oracle to SQL Server migration is a two-stage one. The first step is carried out without shutting down the systems. Next, all changes and incremental data added or updated after the last run are migrated to the target database at pre-fixed intervals.
Organizations can choose one based on their specific needs.
