The Benefits And Processes Of Migrating Database Oracle To SQL Server

The Oracle Database Management System (DMS) has long been the mainstay of large and mid-level organizations around the world to sustain their data-driven operations. However, the exponential data usage growth has led to a steep rise in the demand for storage space and high computing power.

To accommodate this growth, businesses must look for alternative strategies that do not require massive additional expenses in installing new hardware and software. Fortunately, it is now possible to get around this problem at minimum cost to business. The solution that has emerged is to move databases to the cloud such as Oracle to SQL Server migration.

Why Should You Migrate Databases From Oracle to SQL Server – The Benefits

There are several benefits of Migrating databases from Oracle to SQL Server. Let us check the main ones in some detail.

# The first is the cost factor which is very important in the highly competitive business environment today. The cost of running the Oracle database system is considerably more than the SQL Server. This is because the costs of SQL Server are kept within reasonable limits through virtualizing servers, data compression, and consolidation of databases. Further, SQL Server does not require constant monitoring by DBAs unlike Oracle and hence recurring costs are controlled.

# SQL Server has data compression facilities that substantially improve database performance.

# SQL Server has enhanced data safety and security capabilities made possible through complex and encrypted algorithms. Classified business data is firewalled through a series of user access management processes.

# Coming back once more to the cost factor, SQL Server offers more editions to match the precise needs of businesses. For example, the expensive Enterprise SQL edition crammed with cutting-edge features is for large data-driven organizations while the less costly Standard edition is for mid-sized companies. Then there is the free Express SQL server version with few features, ideal for small businesses and start-ups. Hence, organizations can choose one that matches their requirements without paying more for features they will not require soon. Comparatively, Oracle offers standard editions with features that you have to pay for might but not use.

# A key reason for migrating databases from Oracle to SQL Server is the ability of the latter to restore or recover lost or damaged databases and bring them back to the system. This is how it works. The SQL Server database engine allows running queries and data storage through indexes, files, and transactions. The advantage here over Oracle is that log records are written on a disk before a transaction goes through. In case there is a system crash or data outage, these transaction logs are used by the instance after the systems are restored to bring back incomplete transactions from the point where the system was disrupted.

# All that it takes to install the SQL ServerSQL Server is a Setup wizard that does not require command-line configurations. Any updates subsequently are automatically downloaded.

Because of all these benefits offered by SQL Server over Oracle, it makes sense to migrate databases from Oracle to SQL Server.

How to Migrate Databases From Oracle to SQL Server

The migration activity has to be done in two parts, the first is preparing the systems for moving the data and after that, migrating the database. Let us check them individually.

Preparing the system for migrating Oracle database to Microsoft SQL Server

# Install SQL Server in the target database. Ensure there is seamless connectivity and accessibility between the source Oracle database and the target SQL Server.

# Install Oracle Client and SQL Server Migration Assistant (SSMA) in the target server.

# Before launching SSMA and linking it to the Oracle database at source, double-check the port connectivity and any firewall issues.

# Map the Oracle schema where the Oracle to SQL Server migration will be carried out.

# Convert and load all Oracle database objects to the SQL Server. Do this either by synchronizing all database objects or saving a script and running it on the SQL Server.

All these tasks are to be necessarily completed before the next stage of data migration is taken up.

Migrating Database From Oracle to SQL Server

There are two methods that the migration may be carried out and organizations must select one based on their needs.

# One-time method where the whole migration is done in one go. Here, all systems have to be shut down during the tenure of the complete migration process as otherwise, all transactions made after the last backup will not be reflected in the target database.

While this method is easy and seamless, there is a downside too and that is all systems have to be temporarily shut down. This might be inconvenient for large data-driven organizations as their operating efficiencies will be greatly hampered. Moreover, it is also necessary for this one-time Oracle to SQL Server migration method to carry out test executions to ensure that no problems arise during the main migration of databases.

# The second is the phased migration method and involves the execution of two stages. First, the entire database is migrated from the source to the target while the systems are running. Next, all the incremental data which is generated in the source database after the last migration run is loaded continually to the target database at preset intervals.

After the migration of the database from Oracle to SQL Server is completed, verify the process to make sure that there are no data type mismatches or differences.