You might have successfully used your database before your business expanded. However, as your data expands, more applications are added and analytics becomes increasingly relevant, and those old confinements begin to assert themselves.
- Queries slow down.
- Maintaining infrastructure becomes cost-intensive.
- Increased complexity of integrations.
- Greater complexity of integrations.
Then one day, the very same database that once was a strong pillar of your business is becoming a hindrance.
That’s when you may start considering database migration.
Database migration involves transporting your data, database schemas and associated workloads from one environment to another. There could be a mix of moving an on-prem database to the cloud, migrating to a different database technology, upgrading an existing one or integrating data into a modern data platform.
This is just the movement; it’s not the end of it. It’s about ensuring your applications continue to function, your data is correct, and your business is minimally impacted.
What Is Database Migration?
Migration of database components and data from the source environment to the target environment is called database migration. It is not mandatory that the source and target uses the same technology.
For example, you could move an on-premises SQL Server database to a cloud database. An alternative approach might be to transform one relational data store to another or to extract data from an operational data store to a more contemporary platform like Databricks or Snowflake.
If you need to migrate, you can do so depending on your project:
- Tables and records
- Database schemas
- Views and indexes
- Stored procedures and functions
- Constraints
- User roles and permissions
- Application connections
- Data transformation logic
- Integration dependencies
As I’ve found, the data is seldom the only thing to consider. Migration can be significantly more complex if there are a number of applications, reports, integrations and processes linked to that database.
Why Do You Need Database Migration?
One doesn’t typically move a database for the sake of obtaining a new system. There is normally a business or technical problem behind the decision. You may have an aging database you have to pay a lot to maintain. Maybe the current infrastructure isn’t scalable enough for the amount of data. Or, your organization has resolved to migrate to cloud technology.
Some of the typical motivations behind a database move are:
- You Need to Modernize Legacy Infrastructure
- As vendors decrease support for older versions of databases, and different applications require each one to meet new needs, older databases can be hard to maintain.
- Migration allows you to upgrade the old infrastructure and implement technology that meets the newest needs.
- You Want to Move to the Cloud
- By migrating to the cloud, you gain greater flexibility for computing, storage, availability and management of your infrastructure.
- However, don’t automatically move a database to the cloud because of performance or cost issues. Target architecture must still complement your workload.
- Your Data Has Outgrown the Existing Environment
- As your data center grows larger, with more transactions, more users and analytical operations you may need an architecture that can perform better.
- You Want a Modern Data Architecture
Moving data from legacy operational databases to new platforms, such as those that do analytics and AI workloads, may be necessary if a data warehouse, data lake, or lakehouse is being created.
What Are the Types of Database Migration?
You start out based on your current environment and what you want to accomplish with your new environment, and the types of database migration you’re going to consider will depend on both of those.
On-Premises to Cloud Migration
You’re moving your database from infrastructure in your own data center to a cloud-based database or data platform. While this can minimize requirements for managing physical infrastructure, planning for these other components of networking and security, application compatibility and data transfer will still be required.
Cloud-to-Cloud Migration
This is when you’re moving your database or workload between cloud services or cloud providers. This can be done when your cloud plan has evolved, your service doesn’t fit the bill or another cloud service has more features that work for your workload.
The challenge is to get them to work together. On the surface, two cloud database services can appear to be identical, but their internal operations can differ greatly.
Database-to-Database Migration
This means changing the database technology on which the system relies. For instance, you could switch from one relational database to another or from a traditional database to a cloud-based system.
At this point, consider the following during testing of such migration: application dependencies, indexes, stored procedures, SQL queries and data types. Unexpected issues may occur due to small differences.
Database Version Migration
It’s possible that a completely different database isn’t necessary. At times, one may need to upgrade the old database to a newer version. You can obtain new functionality, enhanced security, performance, and ongoing vendor support.
Data Center Migration
If you need to transfer infrastructure between two physical data centres, you might need to transfer your databases and supporting infrastructure too. It frequently occurs in disaster recovery, infrastructure consolidation projects or during a larger modernization initiative.
What Are the Benefits of Database Migration?
If your database migration is a success, it can help you improve a few aspects of your technology.
Better Scalability
As the number of users, data and workloads grows, a modern database platform can provide enhanced flexibility.
Improved Performance
Switching from old storage systems to new ones, or from older databases to newer ones can help to make query performance and data processing more efficient. But this is where testing can come in handy. Poorly designed queries or poor-performing workloads will not necessarily be resolved by a migration.
Lower Infrastructure Overhead
Switching to cloud-based managed services, or upgrading to older equipment when that is an issue, might mean less effort for keeping physical equipment up and running.
Better Data Management
New solutions that run on modern platforms can offer enhanced data integration, monitoring, governance, security, and analytics features.
More Flexibility
There is the option to select infrastructure and services that better suit your workload, rather than trying to shoehorn it into an architecture built years ago.
What Are the Challenges of Database Migration?
This is the one that you will not want to underestimate. Data integrity is certainly one of your foremost issues. The data that you have migrated should be complete, accurate and consistent with the source system. There’s another issue of compatibility. Data types, SQL syntax, functions, indexes or stored procedures might be different in your target platform. Downtime also matters. You need a migration approach that minimises service disruption if your applications rely on it on an ongoing basis.
Typically, what happens in the field is that things that shouldn’t be a problem are actually due to dependencies. The following are the characteristics to search for:
- Application dependencies
- Data quality problems
- Schema differences
- Large data volumes
- Security compliance needs
- Network limitations
- Performance differences
- Reporting and interdependencies between systems
How Should You Plan a Database Migration?
Know your environment before you move. First, determine what databases, applications, integrations, users, data volumes and connections you have. After that, set a clear definition of success for your project. A good database migration approach typically goes through these steps:
- Evaluate current environment & record dependencies.
- Establish migration objectives and outcomes.
- Choose the target platforms according to workload and business needs.
- Draw your schemas and pinpoint problems of compatibility.
- Determine how you’ll migrate and do so with a time out.
- Test the migration first, before touching production.
- Check your data following transfer.
- Transfer production work, roll out with an approved plan.
- Track down the new environment to check on performance, errors and data issues.
Remember, testing isn’t a checkbox; it’s an integral part of the process. Test real workload(s) on the target environment before migration day. This is where complexity and usability issues may be apparent.
Final Thoughts
Database migration can ease the way to modernizing legacy infrastructure, cloud migrations, scalability, and analytics and AI readiness.
However, a successful migration is not just about getting your data from A to B; you have to understand your dependencies, pick the correct migration approach, test your workloads, and then verify before you say that a migration has been completed.
If you are considering Databricks, data platforms, and modern data architecture as modern approaches to databases and data engineering for your business, explore the top Databricks consulting companies on BricksPerformers.
