What Is Data Migration: A Detailed Look Into the Process

What is data migration? Who is it for, and more importantly, how do you even go about doing it? 

Given how difficult these questions can be to answer, we wanted to create a detailed guide on everything data migration. So we’re going to be talking about all the different types, the process from start to finish, the tools you need, and the pitfalls to avoid. So without further ado, let’s get into it!

What Is Data Migration?

First things first, what is data migration? While there are various definitions of the same concept, the simplest one is that it’s a process that describes transferring internal data from one storage system to another.

The process of migrating data also includes data preparation, transformation, and extraction. It’s usually done when an organization wants to introduce a new system or process.

On paper, data migration sounds like a straightforward process. But as it requires a change in storage, database, and/or application, there’s a lot that goes into it.

Why Is Data Migration Important?

The general goal of data migration, no matter the exact purpose, is to enhance a business’s performance and competitiveness. But to break it down, and dive even deeper into the question of what is data migration, here are four specific things it can do for you.

  1. Increase Agility

As technology changes, so does the need to improve its processes. By having a finer, smoother way to transfer data among platforms and by upgrading those same platforms, a business can become more agile. What’s more, it can avoid getting locked into specific systems and vendors that simply might not be working anymore.

  1. Reduce Cost

As a rule, older, out-of-date technologies tend to cost more to operate and maintain. That’s why, when asking what is data migration, we also have to take budgetary restraints into consideration.

If you move data to the cloud or an app, for example, you can save money on both labor and hardware. Using an ETL tool, which we’ll get into more a bit later, will allow you to move your data to a new location, in turn, cutting down on data storage costs.

  1. Improve Collaboration 

Once data storing and migrating becomes more transparent, it can improve department communication. It helps to give visibility into what’s happening in the business and allows for better collaboration.

Types of Data Migration

We can’t properly answer the question: What is data migration? without delving deep into all the types there are. Choosing the right type is a critical step in the strategy because it will determine just how much time your IT department will be able to devote to other projects.

Storage Migration

Storage migration is a term that describes the process of a business investing in a new tech system and getting rid of its old one. Data is moved from one system to the next, and all of the paperwork now becomes computerized.

To give an example, it’s when an organization transfers all of its data from a hard drive to the cloud or to an SSD.

Many businesses use this approach because they want a technological upgrade, not just because they lack storage. Usually, the process doesn’t alter any of the content or the format. 

Another benefit of doing storage migration is that it’s a good opportunity to do data cleaning, data validation, and cloning.

Of course, larger organizations will need more time to migrate their data storage as it’s a pretty time-consuming process. In some cases, it can even last 10 years.

Cloud Migration

Now, cloud migration, as the name would imply, is a term that refers to data transferring from its current location to the cloud. Countless companies have decided to take the step and move their data to the cloud because it provides a lot of storage space for a pretty low price.

In fact, cloud migration is so much on the rise that experts predict the majority of bigger corporations will be operating from the cloud by 2030.

The amount of time it takes to move something to the cloud is directly linked to the amount of potential cloud data. Smaller amounts can be transferred in a matter of hours, but bigger projects can take even up to a year.

Database Migration 

A database is essentially data storage media in which data is organized and structured in a particular way. Database management systems or DBMS head all databases and play a key role in the migration.

When we’re answering the question of what is data migration, we’re often referring to the move from one DBMS to another. Also, it can describe the process of upgrading the current version of DBMS to the latest one. 

Of course, it’s more difficult to change the entire system than simply update an old one. It is extremely challenging when an organization uses data migration software to migrate from a network database, a hierarchy, or a flat file to a relational database. 

Even though the source target systems are outdated, you can still see them in companies across the world. That’s because the entire process of redesigning and moving data can have a steep price.

Application Migration

When an organization goes through a change in its application vendor or software, they tend to do application migration. It’s a process that requires moving data from one computing environment to a new one.

After migration, there are going to be new application interactions, which will require a drastic transformation of the platform. The biggest challenge for application migration comes from the fact that former and target infrastructures can have distinctive data models and formats.

A vendor could and should provide application programming interfaces or APIs to protect data integrity. Given how complex application migration can be, it should always be carried out by a professional, like Coherence Inc.

Data Center Migration

When a data center infrastructure is moved to a new physical location, it’s referred to as data center migration. It’s a term that can also describe moving or transferring data from an old data center infrastructure to new equipment while remaining at the same location.

A data center plays a critical role in an organization as it houses data storage infrastructure, which maintains critical applications. Some of the things you can find in a typical data center include:

  • Servers
  • Storage devices
  • Network routers
  • Computers

Business Process Migration 

When two companies merge, one or both organizations have to transfer information to a new system. They do so to enter new markets and remain competitive. 

That transfer is what we refer to as a business process migration. It requires moving business applications and all data on business metrics and processes to a different environment. The metrics that we most commonly see moved are customer, operational, and product information. 

The Data Migration Process

Now it’s time to get into the nitty-gritty to answer the question of what is data migration. The entire process should be well thought out, seamless, and efficient. That’s the only way to ensure there are no budget overruns or that the process doesn’t stretch out for too long.

The process follows these steps:

  1. Pre-migration planning
  2. Data inspection
  3. Data backup
  4. Migration process design
  5. Execution and validation
  6. Decommissioning and monitoring


When coming up with a timeframe for the migration, you should consider which method you’re using, the size and complexity of the data, key players, and delivery time.

Data migration can also follow the ETL process, which goes as follow:

  • Extracting data
  • Transforming data
  • Loading data


The good thing about using the ETL process and tools is that they can manage the entire, complex process. From profiling and processing massive datasets, all the way to multiple platform applications.

Now’s also the time to figure out which method you’d like to use. You can take your pick from the Big Bang or Trickle data migration approaches.

Big Bang Data Migration

With the Big Bang approach, you would move data from the current environment to the target one in a single swoop. It’s the quicker, less complex, and less expensive process of the two.

Since the migration is being done all at once, it means systems would be down and unavailable to users for a while. That’s why it’s a good idea to do it during public holidays or at times when you expect there to be no or very little traffic.

Of course, that’s not always possible, especially for larger organizations, which is why they opt for the Trickle method. But we’ll get to that in a second.

For all of the benefits Big Bang has, there’s also a massive fault, and that’s the risk of expensive failure. Sometimes, big data can overwhelm the network during transmission, causing it to crash.

That’s why we usually only recommend the Big Bang for smaller companies that have a smaller amount of data. Also, this approach should never be used if the organization has a system that can’t sustain any downtime.

Trickle Data Migration 

On the other hand, we have the Trickle approach, which is based on doing things in phases. It breaks down the entire migration process into sub-process, and that’s where the data transfers happen in small increments.

Unlike with the Big Bang, systems can stay operational while the migration is taking place. There is no downtime in the live system, and since it’s down bit by bit, the approach is less susceptible to unexpected crashes or errors.

Unfortunately, since the process is broken down into so many stages and increments, it is pretty complex and takes a longer time to complete. Even so, it’s potentially the only option for bigger companies that can’t afford any downtime. 

Pre-Migration Planning

In the pre-migration phase, there’s an evaluation of existing and current data sets to test their stability. Experts carry out an analysis of the source and target systems while setting up data standards that will spot any potential problems.Also, this is the stage where the organization decides whether they’ll do the Big Bang or Trickle approach. But most importantly, it’s when all deadlines, budgets, and schedules are set.

Data Inspection

During data inspection, we look into the scope of the data that’s supposed to be migrated. Here, it’s important to see what the qualities or anomalies of the data are, as well as if there are any potential duplications or conflicts. If the volume of these duplicates or conflicts is pretty high, there are certain software application tools that can clean them. But more on that later as we answer the question of what is data migration.

Data Backup

As the name implies, during the backup, the organization needs to ensure that its data is backed up and secure. It’s a safety measure that eliminates the risk of data loss or migration failure.

Migration Design

In the migration design process, you’ll be specifying testing rules, assigning roles and responsibilities, and clarifying acceptance criteria. This is the stage when many companies opt to use ETL, and hire or appoint a software engineer or ETL developer. 

During the design stage, developers will carry out data mapping, they will create scripts for the transition, and choose/customize ETL tools. The duration of this phase will mostly depend on the time it takes to write script procedures or get the right automation tools. 

With all the required software, tools, and personnel, the design process might only take a few weeks. But it could also be a few months.

Execution and Validation

Once all the prep work has been taken care of, it’s time to initiate the migration process. It’s also when the ETL process goes live.

As we mentioned earlier, the amount of time it will take to complete this stage will mostly depend on the amount of data and the chosen approach. Monitoring and validating the process throughout is key to avoiding any failures.

One way to do that is by being in constant communication with other departments. When migration is complete, developers also need to carry out validation and ensure that it’s been executed per set guidelines.

Decommissioning and Monitoring

The final stage includes shutting down the old system and officially putting it out of commission.

The Tools for Data Migration

Another key aspect that goes into answering the question of what is data migration is the tools. The tools you use will prove to be just as important as the approach itself. With that said, here are the three types of migration tools you should be considering.

  1. Self-Scripted

In the past, data migration was often done without the use of any external tools. It was extracted into an intermediary location, and it was loaded into the target location record-by-record.

Developers would still need to do the ETL process, but they’d have to use self-scripted tools. Now, these tools can be useful when moving small amounts of data and when there are virtually no other requirements.

An upside to using self-scripted tools is that they can be developed quickly, and they’re pretty flexible. However, they also add to the test time and can cause issues during scalability.

  1. Cloud-Based

With cloud-based tools, developers can migrate data from an on-premise infrastructure or a cloud to another cloud. Some tools even allow moving data between platforms and many other scenarios.

Cloud-based tools are extremely flexible because developers can process various types of data. They also scale more easily compared to self-scripted or on-premise tools.

The main issue with using these tools is data security. Plenty of things can go awry while data is in-flight. That’s why it’s crucial to understand data protection and automatic vs. configurable security.

  1. On-Premise

One of the biggest benefits of using on-premise tools is that they have security or compliance standards, while cloud-based products don’t. Before the cloud was even a thing, all platforms were hosted on-premise, which is what gave rise to these products.

Another upside to using on-premise tools is that allow for a pretty high level of customization. What’s more, developers can customize both the infrastructure and application layers.

Of course, as with other tools, there are some disadvantages, namely that on-premise tools are pretty costly. Also, there’s limited scalability, and all maintenance, whether it’s to the platform or the infrastructure, has to be handled internally.

Best Practices

We can’t properly answer the question of what is data migration without highlighting some of the best practices:

  • Back up: The most important part of any data migration is not losing data. Ever. In case something goes wrong, you’ll want to back up all your data. You should also check that there are enough resources for it beforehand and that everything has been tested.
  • Clean the data: A migration gives you the perfect chance to clean data and raise its quality standard. That way, you can ensure you’re not transmitting any low-quality data to the new infrastructure.
  • Follow the strategy: There have been countless accounts of data managers abandoning their strategy mid-way through a migration. And while you should always be prepared for the unexpected, it’s never a good idea to abandon a well-thought-out plan as soon as something goes wrong.
  • Keep testing: One thing about migration is that it requires constant and consistent testing. In fact, you should be testing during planning, design, implementation, and maintenance. Always check to see if what’s happening right now is going to give you the best possible outcome.
  • Switching off: Once you have confirmation that the migration has been a success, only then can you switch off the old system. That’s because the previous system is a type of backup in itself. If for any reason, the migration failed, at least you’ll have the old system to fall back on, and won’t have unnecessary downtime.

Potential Pitfalls of Data Migration

As we’ve mentioned throughout, one of the biggest concerns when doing data migration is data loss. That’s why planning and backing up are key steps during the process.

There can also be the issue of a long migration time. From a few months to several years, this taxing process can take a lot out of an organization. Some things that can affect the time include network blockages, connection speeds, and infrastructure limitations.

There’s also always the question of data security, which is why it’s so important to encrypt all information before migration.

Another concern for many organizations has to be budget expectations and overruns. Unforeseen software or personnel costs can wipe out an entire budget and threaten the migration process. 

To Sum Up: What Is Data Migration?

Hopefully, by now, we’ve answered the question of what is data migration and what benefits it can bring to my business.

With its extensive benefits, including cutting down on costs, optimizing platforms, and increasing agility, data migration can be the key to success. But given just how complex it is and everything it takes to pull off a successful operation, it should only be done by an expert.

Professional data managers, engineers, and developers can make the transformation as seamless as possible. They can ensure the project remains on budget and on schedule while following the highest security protocols. 

Experts can ensure that there’s no unnecessary data loss during migration and that the systems keep operating no matter what.

But where and how do you find these experts?

Why Choose Coherence Inc?

Having answered the question of what is data migration, it is now time to get down to business. And who better to take care of it than us?

The Coherence team consists of experts and masters of migration, who can handle every challenge, no matter how big or small. We offer discovery sessions to collect the data, which helps during the architecture stage.

We also have custom tools and product add-ons, which can significantly reduce the duration and impact of migration. What’s more, we will oversee and manage the entire project that we can tailor to your needs.

But that’s not all!

If you don’t want to trust a third party to lead your migration, we’re more than happy to guide you through the entire process. We offer workshops and lab testing, offering only the best solution approaches. 

So get in touch with us and start your data migration today!