Database Migration – What It Is, Understanding Needs, and Challenges
Applications using a database would require updates over time to support new features or fix the scaling problem with the queries. Generally, most companies face this situation as their users grow. As a result, developers have to make the required changes and updates during software development.
You must be wondering why there is a need for database migration while evolving using new and emerging technologies. Let me just brief you about some of the reasons why firms need to migrate databases from one platform to another.
Database migration, in simple words, means moving data from one platform to another. Otherwise, it is a complex, multiphase process, which usually includes assessment, database schema conversion (if you are changing engines), script conversion, data migration, functional testing, performance tuning, and many other steps.
With the rise in popularity of Git, the trend of writing web-based applications using object-relational mapping (ORM) libraries also became well-known. The main objective was: if developers can make changes in code that are easy to roll back using Git, they could also be able to do the same things when it comes to schema changes.
Well, any new feature involves code and schema changes. Therefore, many popular frameworks added ORM and database migration (also known as schema migration or db migration) as part of their offerings.
But, database migration is a concept that is not restricted to popular web frameworks. In order to ease the process of database migration, there are many standalone libraries available.
Let me tell you db migration involves a lot of effort. Performing database migration might seem to be a challenging task for many. And, it is indeed!
The competitive world has given organizations some of the obvious reasons to adopt new technologies. These include speed of doing things, improvisation of overall performance, etc. Now you know what is database migration, it’s time to know reasons for performing database migration. Let’s have a look at them.
1. To Save expenses:
Using old databases might add overhead expenses to the company. Like installing other applications or systems to work in a quick manner. They will move their database to a platform that will serve their purpose in an efficient manner. This will help in saving on infrastructure as well as manpower and expertise needed to support it.
For instance, Evernote, since its inception has maintained its own servers and network. Over time they observed how their operations are getting limited by its infrastructure. They really found it difficult to scale, time consuming and expensive to maintain. They wanted to have more flexibility along with the improving
They wanted to have more flexibility, as well as to improve the application’s speed, reliability, security and disaster recovery planning.
To avoid or minimize the service disruption, they opted for conducting on-premise to cloud migration as efficiently as possible.
2. Upgrade to new technology
This is a very common reason for migration, where the company would shift from either an outdated system or a legacy one to a system that is designed for the current day data needs.
In this era of big data, adopting new and efficient storage techniques is a necessity. For instance, a company might choose to move from a legacy SQL database to a data lake or any other flexible system.
3. To Reduce Redundancy
Data migration is an essential thing for the companies in order to move all the company data to a single place. This will help in minimizing redundant data. Also, the data stored in one place can be easily accessible by all the divisions of the company.
Sometimes, this happens after acquisition when the systems need to be combined. It can also happen when different systems are siloed throughout a company.
For instance, different departments have different databases and there is no sync between them. It becomes really difficult to gain insights from your data when you have different databases that are incompatible.
4. Security Fixes:
As per the research, it is found that the databases are one of the most vulnerable entities to cyberattacks. This is because they are the easiest to get into through networks. Most of the organizations fail to upgrade their databases regularly as they do other systems. This eventually leaves a wide gap for the hackers to enter and reveal or steal information.
Mike Dietrich of Oracle states, “The news is full of reports [about] hacked and cracked systems. It is essential to have the most current security fixes”.
Most of the database upgrades come with security options, which implies that the only way to protect your database is to get it updated on a regular basis.
For instance, when Oracle upgraded to the 12g version, many users were happy with the improved productivity that the features provided. A Senior Oracle Instructor at New Horizon University pointed out that the new version allowed pluggable databases. The organizing categories and individual entries are much easier and quicker. Organizing databases readily implies that the information is fetched easily, thereby, enhancing productivity.
If you find any of the above reasons (among many) hurdling your overall application performance, then you should go for db migration.
Since database migration is a very complex task, it is obvious to face different challenges during the process. Many of us might be aware of the challenges involved in the process, but very few might know how to overcome those. Some of the common challenges are as follows:
1. Identification of Databases stored at different places
With the passage of time, every company gathers some amount of data. If your company has been operational for a while, there is a possibility that the data is housed in various databases across different levels within the organization. The biggest challenge in migrating the databases is identifying the location of the databases in your environment. Also, after identification, it is a tough task to decide how to normalize and convert the schemas.
2. Data Analysis at the earliest
Sometimes, information can be hidden in obscure places, due to constraints in computer systems. This happens because there aren’t specific fields to hold all elements of the data or users may not be aware of the purpose of the available fields.
Consequently, the information transferred during the migration will be incomplete, inaccurate and outdated, often discovered very late in the day, even after the project has been completed. The outcome might not have enough time or the right resources to be able to identify and correct this data.
It is one of the Database Migration Best Practices to perform thorough data analysis at the earliest possible occasion, usually when planning and designing the data migration. It can help you in unveiling these hidden errors.
3. Devising a migration strategy
Database Migration is a strategic process. It is fraught with a lot of risks. Devising a plan for safe, secure and efficient migration of databases is really important for the migration to be successful. Well, for many teams deciding whether to pursue a “big bang” migration – a single step process or to leverage a more methodical, incremental approach called a “trickle” or “parallel run” migration.
There are various factors that can influence the migration strategy such as allocated budget, timeline or time constraints, and available human resources to execute the migration.
“According to research, enterprise db migration projects can cost up to $875K and experience more than $250K in cost overruns.”
Financial and time implications can add another layer of complexity to the planning and strategy process.
4. Lack of Integrated Process
A typical process of data migration involves different people using myriad technologies. For instance, the use of spreadsheets to document data, which are usually prone to human errors and are difficult to be translated doing data analysis or performing data transformations.
The use of various technologies can sometimes lead to failure in the transfer of data and its design between the analysis, development, testing and implementation phases. Sometimes things get lost in translation which eventually increases the cost and wastes a lot of time. For this, organizations should look to utilize the platform at its full potential. It should be able to successfully link the critical inputs and outputs from each of the stages to help in reducing the error and save time and money.
5. Data cleaning and coding
Data stored in databases might be in different formats that would have come from varied sources. The data coming from various places needs to be cleansed, normalized or transformed. This should be done in such a manner that allows you to analyze it together with data from other sources.
In such cases, you might need to adapt to your data model to account for a mix of structured or unstructured data, or for any discrepancies that might occur while moving from one database to another.
6. Not evaluating final results in a timely manner
This can only happen in the testing stage. The users can see the actual data that will be loaded into the new system at the end of design and development. At this point, the incompatibility of the data in the new system is one of the worst outcomes that can arise.
An organization can work without finding a solution to the problem, but speaking frankly this is not the best practice. Early and agile testing phases like Test-driven Development can be introduced to reduce the rework in the project. Further, getting your users involved in evolving the test cases as they see the actual prototypes of the data output.
7. Lack of collaboration
As mentioned, data migration involves different people who use different technologies. In some cases, a mix of your employees and some external engineers would work on db migration. It might happen that some of these people may not be in the same location. Working at different locations in silos might impact the overall efficiency, create more data silos, and can lead to misinterpretations. While working together, it can be difficult to deal with situations when things go wrong.
Most people try to blame rather than resolving issues. Making use of collaborative tools helps the parties involved in the migration in observing the same picture of data as it moves through various project stages, leaving little or no room for assumptions and misunderstandings.
8. Emphasize more on data analysis/ Take help from data experts
A data migration project is a challenging and high-risk task. It would be better to introduce data experts in your migration projects right from the start. This will ensure they make sense of disparate data sources and guide the data transformation that would be appropriate for the audience who will be using it in the target system.
It makes sense to seek experts but it is usually applied to the management and technical aspects of data migration. However, these experts, who are usually hidden in business don’t appear until late in the day. Also, those with access to data are unable to decode it, while those that are unable to obtain access to it, sometimes because the system is not ready.
Well, if these hurdles are dealt with during the planning stage and are overcome early before the data is transformed or transferred, you can be sure of success.
9. Securing data and systems
Data migration isn’t just time-consuming and costly but also has the potential for increased risk without the right protocols and plans in place. In any migration, there is a treasure trove of high-value intellectual property that has the risk of being leaked, lost or otherwise accessed by unauthorized users (either inadvertently or with malicious intent). Any of the instances could mean significant damage to the company reputation, customer churn or even potential lawsuits or punitive fines.
For instance, Twitter migrated from MySQL to its custom database Manhattan. The lesson that they learned,
“Over the years, as we’ve migrated data from MySQL to Manhattan to take advantage of better availability, lower latency, and easier development, we’ve also adopted additional storage engines (LSM, b+tree…) to better serve our traffic patterns. Additionally, we’ve learned from incidents and have started protecting our storage layers from abuse by sending a backpressure signal and enabling query filtering.”
If you are planning to migrate your database, then you should gather all the information required to successfully complete the project. I have segmented the database migration steps into three,
- Pre-migration steps
These steps should be taken before actually migrating the database, which will include the basic planning, structuring, understanding the requirements, and finalizing the move.
- Migration Steps
These are the steps that are to be taken while implementing database migration. These steps should be accomplished with proper accountability taking utmost care about data governance roles, risks related to migration, etc.
- Post-migration steps
Once db migration is complete, there might be some issues that would have gone unnoticed during the process. These steps would be necessarily taken to ensure that the migration process gets over in an error-free manner.
For further reading, you can refer – How does database migration work? [ultimate checklist]
In the previous section, we discussed how database migration works with a step-by-step guide. However, to implement this methodology, multiple database migration tools are available in the market; however, making a choice could be daunting. In this section, let’s look at some of the top database migration tools of all time.
Top Database Migration Tools
1. AWS Data Migration
AWS Data Migration is one of the most popular suites of migration tools that are a part of the AWS ecosystem. It is a highly suitable cloud data migration tool as it offers hybrid cloud storage, online data transfer, and offline data transfer. In addition to that, it has a variety of services that helps you move datasets, irrespective of their type.
AWS Database Migration Services starts at a meager cost. You only need to pay for the instances you utilize. Also, when you’re migrating data to any AWS-based database, you can use DMS free for six months. For more info, visit this link.
- It helps you to minimize application downtime to a large extent.
- Supports both homogeneous as well as heterogeneous database migrations.
- Suitable for continuous data migration due to its high availability.
- Built-in security facility for data at rest as well as during migration.
- Doesn’t support schema migration or conversion.
- Requires coding for incremental data capture.
- Only replicates a limited amount of DDL (data definition language).
- May slowdown system when used for a vast amount of data.
2. Informix (IBM)
Informix is another excellent data migration tool developed by IBM to move the data from one IBM database to another. It primarily focuses on homogeneous data migrations and suitable for relational, object-relational, and dimensional databases. In addition to all these, Informix is a high-speed and flexible database that can easily integrate with SQL, NoSQL or JSON, and spatial data. Right from an enterprise warehouse to a standalone application, Informix works well.
There are four major pricing plans available for Informix – Small, Medium, Large, and Extra Large. However, the pricing varies according to the region, and each plan will offer you a variety of features. For knowing more about the pricing, visit this page.
- Highly scalable and very easy to maintain for a newbie.
- Supports database migration between various operating systems.
- Facilitates data migration from one server to another.
- Has one of the best data replication techniques.
- Doesn’t have the full backing of IBM, although it’s their product.
- Very difficult to find any missing functionality.
- Doesn’t update its features regularly.
- A very complex pricing policy.
3. Azure Database Migration Service
Owned by the tech giant Microsoft, the Azure Database Migration Service is a database migration tool that allows you to simplify and automate the migration to Azure. With the help of this tool, you can easily migrate data, schema, or objects from multiple sources to the cloud. In addition to all these functions, it provides support for migration from SQL Server, MySQL, PostgreSQL, MongoDB, and oracle to the Azure cloud.
Azure Database Migration Service offers two types of pricing models – Standard Compute that supports offline only migrations and Premium Compute that supports both online and offline migrations. Also, the price varies according to the region To know more, visit this link.
- Executes complete migration within zero downtime.
- Useful even for a newbie as the migration process is easy to execute.
- Support for both homogenous and heterogeneous database migration.
- High availability as well as scalability.
- Pricing plans are not categorized according to the size of the business.
- The user interface for Azure is highly complex.
- The initial setup takes a long time almost close to 10 minutes.
- Limitation on the size of the database you can operate.
4. IRI NextForm
IRI NextForm is one of the finest database migration products that allows you to convert, replicate, and report the data within a GUI. One can use the NextForm tool for converting file formats, legacy data stores, data types, database schemas, and much more. In addition to that, NextForm helps you free yourself from the vendor lock-in problem and allows you to cull your data, thereby reducing the storage and optimizing the I/O.
There are six major editions available for IRI NextForm – Lite, COBOL, DBMS, Legacy, Modern, and Premium. For all of these editions, the tool offers free support for one year from the date of purchase. To know in detail, follow this link.
- Supports close to 200 legacy and modern data stores.
- A simple procedure for data definition and metadata manipulation.
- Cross-platform support for Windows, UNIX, and LINUX.
- Allows reusing same data copies without new system regeneration.
- Can be highly confusing for a beginner.
5. DBConvert Studio
DBConvert Studio is a database migration as well as a synchronization tool. It supports on-premises databases such as SQL Server, MySQL, PostgreSQL, Oracle, etc. DBConvert Studio combines battle-proven DBConvert and DBSync Cores with next-level UX design to deliver concrete results. In addition to all these, the tool also supports one-way and bi-directional synchronization to keep the database in sync.
There are three primary options available – Personal ($149), Business ($449), and Enterprise ($999). All the upgrades released within one year of purchase are free of charge for each of these options. To know more about it, visit the pricing page.
- Flexible built-in scheduler for launching tasks at a specific time.
- Allows renaming of database objects during migration.
- Helps you to speed up your database migrations.
- Transfer your valuable data in an error-free manner.
- Not suitable for real-time or on-demand data access scenarios.
Simform is a leading tech company, helping businesses leverage their performance by developing custom software solutions for them including database migration service. We have a team of skilled professionals who can help you in successfully migrating database – starting from the assessment of an existing database to making a roadmap for the database migration. Also, we work with serverless databases.
We ensure that the necessary precautionary steps are taken in order to avoid any data loss during the migration of the database. Our team can consult you in the technologies that are best suited for the type of database that your company owns or will require. After successfully migrating the database, we validate the data stored in the database and repair if any discrepancies have been encountered while performing the migration.