A complete guide on Technology Migration Strategies: (Part 1 – Introduction)
22nd December 20206 mins
Imagine a scenario where you buy a new apartment, you’re all packed to move in, and have carefully planned the process through. You are all set to move to your new home, then suddenly you realize–there is a problem. The furniture and artifacts do not fit well with your new apartment.
How would you feel if you had to dump all your furniture and start from the ground up? Taking this analogy further, consider the new apartment as your new database and the furniture as the data. We are sure that data would be much more important than furniture for your business, and hence you’d want to retain every single bit of it while you plan to migrate.
As a follow continuation of our technology migration series, in this blog, we shall try to uncover the basics of database migration(DBM), and what one should understand, consider and take care of while performing the database migration.
As a follow-up from our previous application migration blog, today’s piece centers around database migration (also known as schema migration) because it’s one of the most important migrations that deals mainly with selecting, extracting, transferring/updating the data from one database framework to another.
Essentially, the need for database migration can be specific to a business requirement, or even to satisfy the latest multiple regulatory policies instituted by various regulators. While there are no defined situations when DBM is needed, we have listed some situations where this is unavoidable:
Migrating the database system to a new platform reduces the disruption occurring to daily business operations. This can be done with minimal manual efforts if the selection of a new database platform is done wisely.
Before proceeding with database migration, let’s first have a look at the different types of databases:
Migrating data from one database platform to another can be a crucial task. If the migration is planned in a LIVE Environment, the migration has to be done with utmost caution. One must choose a convenient migration time before moving forward with data migration. The live systems often experience downtime when the data is being transferred to a new database.
There are mainly two approaches to database migration:
Big Bang Data Migration:
This approach is where one chooses to migrate the complete database at once in a limited time frame. Although big bang data migration seems less complex, it requires sufficient downtime for the live website. Furthermore, with this approach, a complete rollback of the migration process might not be easy to achieve in case the migration fails at any moment.
Trickle Data Migration
With this approach, one has to split the migration process into smaller chunks or phases. Almost like an agile approach to migration, if a single phase fails, then only that phase needs to be rolled back, and the process repeated. However, Trickle data migration is highly time-consuming and thus might increase the project cost.
Relational DB to Relational DB
This approach is the most straightforward migration. There are tons of tools available that perform this type of migration pretty efficiently, and almost 100% effectively.
Relational DB to Non-Relational DB & Vice-versa
This migration is more difficult in comparison to the aforementioned one. Since Relational DB & Non-Relational DB are fundamentally different, their migration may not be 100% efficient. Essentially, migrating to Non-Relational DB means sacrificing the ACID properties (atomic, consistent, isolated, and durable) which guarantee the scalability of a database.
However, there are multiple free tools available that support database migration from Relational to Non-Relational DB. Though using them is not widely recommended as these tools do not support the system’s schema structure and most seem too rigid to adapt to the system’s requirements.
Though there are some basic conversion tips that we can render for this type of migration that we can consider (for ease, let’s consider MySQL as our Relational Database and MongoDB as our Non-relational Database)
Migrating with a Hybrid Model
The hybrid model design integrates the two popular database models in a single framework whilst mitigating the drawbacks of each system. For example, we can always go with a hybrid approach where we can exploit a Relational DB for less demanding operations, in combination with a non-relational DB for data-intensive initiatives.
Planning a migration strategy before execution can ensure a smooth migration process. That being said, we need to always have a Plan B. Assuming a worst-case scenario where there is some data loss, or the data gets corrupted while executing the migration; you must be prepared to restore the data to its original state before trying again. This is why Data Backup is a highly imperative step during the DBM (Database Migration). So, what options exist to ensure secure data backup, let’s delve in.
One of the most efficient and secure methods to protect your migration initiative is to execute a backup to cloud storage. Essentially, when you back up your data to cloud storage, your files are stored off-site. This eliminates local hardware vulnerabilities that may cause problems. So, why a cloud backup?
Software suites like Dropbox are growing to meet the needs of their users. Dropbox maintains versions of files that can be restored when required. Similar to cloud backup, this option is affordable and files are stored offsite. What are its advantages?
A downside, however, is that restoration is not automated. You need to copy & paste the data to the file-sharing directory structure in order to save the data. The files must reside in a defined structure, or else they will not be backed up. If the files are in a shared folder or directory, you will probably require more bandwidth to back up those files.
Generally speaking, there are other available mediums for backing up like a backup to a flash drive or external hard drive. But these options are not recommended as they are not entirely secure compared to cloud backup or file-sharing software. For instance, any physical damage to a hard drive can cause data loss. Furthermore, they are more vulnerable and susceptible to ransomware attacks and crypto-viruses.
When carrying out data migration, you need to make sure that sensitive data is not breached or tampered with. If migration goes wrong, it may lead to greater consequences and result in data leaks or data loss such as the examples cited here in 2020.
Unfortunately, data leaks may cause damage to the client’s reputation, lead to loss of business and customers; or in some cases, may provoke legal actions. To avoid all such consequences, you need to draw up a security plan beforehand keeping in mind the migration strategy.
To ensure secure migration, avoid using primitive tools. Using primitive tools might weaken your system and leave loopholes for hackers to access. You must employ robust tools for data migration that are functionally specific.
Data migration is principally a multiphase process, and following steps should be followed to avoid data loss and ensure safe database migration.
Once the new database is live, a system can be set up to audit the data. This will ensure the accuracy of the database migration and draw attention to incomplete and inaccurate data.
Database Migration is a highly intricate procedure and it comes with its risk and uncertainty. You can always overcome these with proper planning and execution. The risks that can be encountered are:
Migration from a real-time database: For any high-transaction website, migrating the database is always difficult as there are constant data updates taking place, and migrating live & real-time data is not possible. There has to be downtime for any migration to happen.
You can always seek guidance from third-party experts on Database Migration. We are Creole Studios do specialize in Database migrations, and we would be happy to help or consult in any such endeavor. Stay strapped in for the fourth and final blog of the technology migration series.