Explained – Why Should You Migrate Databases From Oracle to SQL Server

The Oracle Database Management System (DBMS) has been the mainstay of data-driven organizations around the world for more than 40 years now. So, is it relevant to ask whether businesses should migrate databases from Oracle to SQL Server? If yes, what benefits does this activity bring to the table?

In this post, you will learn about this form of database migration as well as the process of doing so. 

Taking an overall view of the current business environment, it is seen that organizations, regardless of their size and scale, are largely data-driven, with massive volumes of data being generated every day. This ecosystem requires two attributes to function well. 

First, the IT infrastructure must be very cost-effective to make the investments in hardware and software worth their cost. Second, the database system must be fully secure and safe so that classified and sensitive data is not compromised. In both these cases, database migration from Oracle to SQL Server is an assurance in this regard, along with high data durability and integrity. 

Let us now explore how these two factors – cost effectiveness and data durability and safety – are optimized by migrating databases from Oracle to SQL Server.

Benefits of migrating databases from Oracle to SQL Server

Benefits from technologically advanced features.  

# The SQL Server is user-friendly and easy to install without any command-line configuration. The installation is seamlessly completed by a Setup Wizard, and once the process is completed, all upgrades are automatically downloaded. Comparatively, it is not so simple with Oracle, where additional drivers and applications must be downloaded first before initiating the setup.  

# In SQL Server, it is possible to recover lost data in the event of a database crash or outage.  This is because of the attribute of the database engine that helps to store data with queries being run via files, indexes, and transactions. Hence, when there is an issue with the database functions, it is not difficult to restore and recover lost data. This is a critical reason for organizations preferring to migrate databases from Oracle to SQL Server. 

The data recovery cycle is as follows.

Before a transaction is completed in the SQL server, log records are noted on a disk. When an outage or unexpected break in operation occurs, the transactions help to maintain functional continuity and, hence, there is no break in work or downtime. When the issue is subsequently resolved, the logs restore the database from where the break occurred. This prevents any degradation or data loss from any unfortunate reason. 

# Data security is another area where SQL Server steals a march over the Oracle DBMS. Here, access to the database is strictly controlled through highly effective access management programs, and classified and sensitive data is firewalled optimally. Additionally, SQL Server data is completely encrypted and protected through smart and intelligent algorithms.   

While these technologically advanced features are enough to make organizations migrate databases from Oracle to SQL Server, let us check how SQL Server is also ahead as a cost-effective platform. 

Benefits from cost-effective features

# A cutting-edge feature of SQL Server is data compression to the extent of 10x. Since businesses store huge amounts of data, compression frees up space for more data to be accommodated in a fixed storage volume, approximately one-tenth of what would normally be required. This, along with data consolidation and visualization of servers, leads to substantial savings for businesses.  

# The SQL Server offers several versions of its database management system, thereby allowing users to opt for one that meets their requirements. They do not have to pay high license fees for top-end products that they will not use. 

Let us go by an example for a clearer understanding of this point.

The SQL Server offers several versions at various price points in license fees. At the bottom is the free Express editions with very limited storage and features, but ideal for individuals and startups. Above that is the Standard edition with a low price but more features than the Express edition, just right for small and mid-sized businesses. At the top of the pile is the Enterprise edition with high license fees and cutting-edge features, making it ideal for large companies and corporations. 

Businesses can start from the Express edition and work their way up to expansion without having to spend more for features that they will not use soon. In comparison, Oracle charges a flat licensing fee for storage and other features that must be paid for even if not required. 

Because of this cost-effectiveness, it makes sense to migrate databases from Oracle to SQL Server.   

Migrating Databases from Oracle to SQL Server 

The SQL Server Migration Assistant (SSMA) for Oracle is used to ensure a seamless migration process. The Assistant reviews data and database objects, and accesses databases for migration. However, a more complex groundwork must be prepared by DBAs when SYS and SYSTEM Oracle schemas are involved, as they cannot be migrated straightaway.   

There are two processes that may be followed to migrate databases from Oracle to SQL Server. 

# One-shot method: Here, all systems are shut down and the whole database is migrated in one go. The reason for the downtime is to ensure that all existing data is moved and that no data generated after migration is present in the source database and not moved to the target database. 

# Phased method: Here, Oracle to SQL server migration is done in two stages. First, the data is migrated without shutting down the systems. Next, all incremental data generated after the last migration run is moved from the source to the target database at pre-defined intervals.  

Organizations can choose any one that matches their needs, though large corporations would not want to shut down databases as in the first method.