Hadoop to Snowflake Migration: Challenges, Best Practices, and Practical Guide

Moving data from Hadoop to Snowflake is quite the task, thanks to how different they are in architecture and how they handle data. In our guide, we're diving into these challenges head-on. We'll look at the key differences and what you need to think about strategically. The shift from Hadoop, with its traditional way of processing data, to Snowflake, a top-notch cloud data warehouse platform, comes with its own set of perks and considerations. We're going to break down the core differences in their architecture and data processing languages, which are pivotal to understanding the migration process.   

Plus, we're not just talking tech here. We'll tackle the business side of things too – like how much it's going to cost, managing your data properly, and keeping the business running smoothly during the switch. Our aim is to give you a crystal-clear picture of these challenges. We want to arm you with the knowledge you need for a smooth and successful move from Hadoop to Snowflake.

Common Hadoop to Snowflake migration challenges

Moving from Hadoop to Snowflake requires getting a grip on the technical challenges to produce a smooth transition. To begin, let’s talk about the intricate differences in architecture and data processing capabilities between the two platforms. Getting a handle on these technical details is necessary to craft an effective migration strategy that keeps hiccups to a minimum and really gets the most out of Snowflake's capabilities.

As you shift from Hadoop to Snowflake, you’ll need to adapt your current data workflows and processes to fit Snowflake's unique cloud setup. It's necessary for businesses to keep their data sets intact and consistent during this move. Doing so is key to really tapping into what Snowflake's cloud-native features have to offer. If you maintain high data quality, you'll achieve better data storage, more efficient processing, and seamless data retrieval in your cloud environment.

Architecture differences between Hadoop and Snowflake

Hadoop and Snowflake are like apples and oranges when it comes to managing and processing data. Hadoop focuses on its distributed file system and MapReduce processing. It's built to scale across various machines, but managing it can get pretty complex. Its HDFS (Hadoop Distributed File System) is great for dealing with large volumes of unstructured data. However, you’ll need extra tools to use the data for analytics purposes. 

Snowflake's setup is built for the cloud from the ground up, which lets it split up storage and computing. The separation of these two components means it can scale up or down really easily and adapt as needed. In everyday terms, this makes handling different kinds of workloads fat more efficient and reduces management overhead. All this positions Snowflake as a more streamlined choice for cloud-based data warehousing and analytics.

Hadoop’s architecture explained

Hadoop's architecture, known for its ability to handle big data across distributed systems. It's like a powerhouse when it comes to churning through huge, unstructured datasets. But, it's not all smooth sailing – managing it can get pretty complex, and shifting to cloud-based tech can be a bit of a hurdle. Hadoop stands out because of its modular, cluster-based setup, where data processing and storage are spread out over lots of different nodes. For businesses that really care about keeping their data compatible and moving it around efficiently, these are important points to think about when moving to Snowflake.

Source: https://www.geeksforgeeks.org/hadoop-architecture/

Scalability: Hadoop handles growing data volumes by adding more nodes to the cluster. We call this horizontal scaling. For a lot of businesses, this is a cost-effective way to handle massive amounts of data. But, it's not without its headaches – it brings a whole lot of complexity in managing those clusters and keeping the network communication smooth. And as that cluster gets bigger, keeping everything running smoothly and stable gets trickier.

Performance challenges: Hadoop's performance is highly dependent on how effectively its ecosystem (including HDFS and MapReduce) is managed. When you're dealing with data on a large scale, especially in batch mode, it can take a while, and you might not get the speed you need for real-time analytics. Getting Hadoop tuned just right for peak performance is pretty complex and usually needs some serious tech know-how.

Integration with modern technologies: Hadoop was a game-changer when it first came out in the mid-2000s, but it's had its share of struggles fitting in with the newer, cloud-native architectures. Its design is really focused on batch processing, not so much on real-time analytics. As a result, it doesn't always mesh well with today's fast-paced, flexible data environments.

Snowflake’s architecture explained

Snowflake's architecture is designed as a cloud data warehouse. Its separate storage and computing resources means it’s engineered for enhanced efficiency and flexibility. You can dial its computing power up or down depending on what you need at the moment, which is great for not wasting resources. Plus, Snowflake is optimized for storing data – it cuts down on duplicates, so you end up using less space and saving money compared to Hadoop. All in all, Snowflake is a solid choice for managing big data. It's got the edge in scalability and performance, especially when you stack it up against Hadoop's way of mixing data processing and storage.

Dialect differences between Hadoop SQL and Snowflake SQL

Moving from Hadoop to Snowflake means you've have to tackle several big differences in SQL dialects – the way syntax and functions behave. It requires figuring out how to adjust queries that handle huge datasets from Hadoop’s HiveQL into Snowflake’s SQL style.  As a result, the translation of queries and scripts is a key aspect of the migration process.

Hadoop has its own way of using SQL, mainly through HiveQL, which is tailor-made for handling big data across its distributed setup. However, HiveQL doesn't quite play by the rules of traditional SQL. If you're used to the standard SQL, you might find HiveQL's unique extensions and functions a bit of a curveball. The biggest challenges are usually its non-standard joins, UDFs (User-Defined Functions), and windowing functions. If you're coming from a traditional SQL background, getting the hang of these could require additional learning and adjusting.

Snowflake SQL operates by ANSI standards, and it's fine-tuned for Snowflake's cloud-native data warehousing. Being fine-tuned for Snowflake's cloud-native data warehousing means you get a smooth and efficient experience when you're working with data. It's packed with advanced features like top-notch JSON support, killer window functions, and it scales easily – perfect for all types of complex data analytics. Plus, Snowflake SQL is designed to make query writing and execution a lot simpler, giving you a user-friendly interface that improves your data processing and analysis tasks. 

Dialect differences between Hadoop and Snowflake: Data types

In handling complex data types like arrays and structs, major differences emerge between Hadoop’s HiveQL and Snowflake. HiveQL directly manipulates elements within these types, while Snowflake requires the FLATTEN function for nested structures, reflecting a more SQL-standard approach. The distinction highlights the contrast in querying and data manipulation methods between the two platforms.

HiveQL allows you to dive right in and adjust elements inside these types. But Snowflake plays it differently – you’ll need to use the FLATTEN function to deal with nested structures, which is more in line with standard SQL practices. The distinction highlights the contrast in querying and data manipulation methods between the two platforms.

Example query: Hadoop SQL and Snowflake SQL

In Hadoop's HiveQL, when you need to pull out specific data from complex data structures, you often have to use its special extended syntax and functions.

SELECT get_json_object(source_data_column, '$.key') AS extracted_value
FROM hadoop_table;

The query above demonstrates how HiveQL can extract a value from a JSON object stored in a source data column.

In Snowflake SQL, you'll use a different kind of syntax to query those same kinds of data structures, but at the end of the day, you'll get the same result. It's just a different path to the same destination.

SELECT source_data_column:key::STRING AS extracted_value
FROM snowflake_table;

In this snippet of Snowflake SQL, we're using a neat syntax (::) trick to pull a value out of a JSON object. Although different from what you might be used to, that's just Snowflake's way of dealing with semi-structured data types.

Using a SQL translator to migrate from Hadoop SQL to Snowflake SQL

Using automated SQL translation tools can greatly improve the efficiency and accuracy of moving large codebases to modern platforms. They come with substantial benefits, including:

  1. Reduced development time: By automating the translation process, developers can focus on other aspects of the migration, such as data mapping and testing , rather than spending precious time Googling "date_trunc" in Snowflake.
  2. Minimized errors: Automated tools translate code based on predefined rules and existing libraries, reducing the risk of human error introduced through manual rewriting.
  3. Preserved business logic: Effective translators maintain the core functionality of the original scripts, ensuring business logic remains intact after migration.

Tools like Datafold, which have integrated SQL dialect translators, can really smooth out the process, especially when it comes to complex date calculations and window functions. This kind of functionality is highly beneficial for migrating from Hadoop to Snowflake, where these features are frequently used.

Datafold's SQL translator can translate Hadoop to Snowflake SQL with the click of a button

Business challenges in migrating from Hadoop to Snowflake

Making the move from Hadoop to Snowflake presents a range of business challenges, encompassing more than just the tech but also strategic and organizational aspects. Here's a rundown of the main challenges you might face when migrating your enterprise data: 

Cost implications: Shifting from Hadoop to Snowflake can offer financial advantages down the line, but it's important to recognize that the initial migration stage can be quite costly. Aside from expensive migration tools, organizations should also plan for expenses related to the period when both Hadoop and Snowflake systems may need to run simultaneously. Careful financial planning is key here.

Business continuity: Business users need to keep operational downtime to a minimum during the migration, to make sure business activities aren't thrown off track. This calls for some smart migration planning. Making sure that critical business functions keep humming along smoothly requires careful timing and thorough execution.

Data governance and compliance: Moving to a new data platform like Snowflake brings up key issues around data governance and sticking to regulatory standards. So, it's crucial to make sure that sensitive enterprise data is transferred securely and that Snowflake’s setup ticks all the boxes for compliance throughout the migration process.

Workforce upskilling: Migrating from Hadoop to Snowflake means your team needs to level up or evolve their skills. Snowflake's cloud-based tech and SQL approach are quite different from what Hadoop offers. To tackle this, it's important to invest in thorough training and development programs. Focusing on practical, hands-on experiences in these programs will make sure your team is ready and able to work effectively in the new Snowflake setting.

4 best practices for Hadoop to Snowflake migration

Navigating the shift from Hadoop to Snowflake has its complexities, but with careful planning and execution, it can be both efficient and rewarding. Central to the best practices of this migration is a deep understanding of how Snowflake's data cloud infrastructure can greatly improve data storage, processing, and accessibility. The platform's cloud-native features give it some clear advantages over Hadoop.

Snowflake rethinks how data is stored and accessed, using its cutting-edge data warehouse features to achieve peak performance. Grasping the nuances of this technological shift is crucial as it will impact all future migration decisions and actions, paving the way for a successful and streamlined transition. Now, let's dive into the specific strategies that bring these best practices to life. 

  1. Plan and prioritize asset migration: Planning to move assets from Hadoop to Snowflake requires taking a good, hard look at your current enterprise data assets. A careful review here helps you figure out which ones are critical for your business operations and should be prioritized in the migration. 

    Start off by shifting smaller, simpler datasets over to Snowflake. This lets your team get their bearings in the new setup without too much risk. Going step by step makes the whole migration process more controlled and manageable. Plus, it gives you the chance to tweak and optimize the process as you start handling bigger and more complex data assets.
  1. Lift and shift the data in its current state: Consider going with a 'lift and shift' strategy when moving data from Hadoop to Snowflake. Use this approach to transfer your data ‘as is’ and simplify the first part of the migration. You won't have to worry about transforming or reshuffling your data right off the bat. Businesses that choose this route can expect a faster move of their existing data structures and content into Snowflake. It lays down a great base for fine-tuning and making improvements once you're settled in the new environment.
  2. Document your strategy and action plan: Getting your migration strategy and action plan down on paper is key to keeping everyone on the same page during the shift from Hadoop to Snowflake. Make sure you document everything in detail – spell out each step of the migration, lay out the timelines, who's doing what, and where resources are going. Documenting this process becomes a highly useful reference to monitor progress and ensure a smooth execution.
  3. Leverage automated validation: Use tools like Datafold to maintain data integrity and consistency during the transition from Hadoop to Snowflake. These types of tools provide functionalities for cross-database data comparisons that are invaluable in streamlining the validation process. Automation guarantees the quality of the migrated data and builds stakeholder trust in the new system. The end result is a more seamless transition.
Datafold shows you the value-level differences between two databases, allowing you to find migration issues fast and with great detail

Putting it all together: Hadoop to Snowflake migration guide

To ensure a successful migration from Hadoop to Snowflake, it's crucial to combine technical know-how with some sharp project management. By integrating the best practices highlighted in our guide, your team can navigate this transition smoothly and effectively. Here's a structured approach to synthesizing these elements: 

  1. Plan the migration from Hadoop to Snowflake: Kick off your migration from Hadoop to Snowflake with a detailed plan. Cover every step of the process – think timelines, who's doing what, and the major milestones. Take a good look at your current Hadoop setup and the data you've got.  Understanding your current Hadoop infrastructure and datasets helps you get a clear picture of the migration's scope and complexity, and to determine which data and workloads should be prioritized in the move.

    Set some clear goals for the migration – like boosting performance, cutting costs, or beefing up your data analytics. Setting objectives will help steer your decisions and let you track how successful the migration is. Don't forget to team up with folks from IT, data engineering, and various business units. You want to make sure your plan ticks all the boxes for tech needs and business aims, so everyone's moving together towards the migration.
  1. Prioritize data consumption endpoints first: When you're moving from Hadoop to Snowflake, it's a smart move to start with transferring your data consumption points – think analytics tools and user apps – over to Snowflake first. Businesses that follow this approach really help keep things running smoothly. They get immediate access to their enterprise data in Snowflake, making sure there's no break in service as the rest of the migration keeps rolling.
  2. Adapt data pipelines and ETL for Snowflake: Getting your data pipelines and ETL processes ready for Snowflake means adjusting them to make the most of Snowflake's slick, cloud-native data handling and storage. When you do this, your organization can  fully leverage Snowflake's automatic scaling and optimized query performance. By taking this approach, you're not just moving your data.
  3. Get stakeholder approval: Getting the green light from stakeholders at key stages  during the move from Hadoop to Snowflake is essential. It makes sure everyone's on the same page with the business goals and helps confirm that the transition is going well. Keep your stakeholders in the loop with frequent updates and show them how the system's doing in Snowflake. By engaging them this way, you build their confidence and get solid backing for the migration. (P.S. — there’s no better way to gain stakeholder trust than to show them a Data Diff between Hadoop and Snowflake ;) .)
  4. Deprecate old assets: After you've successfully wrapped up and double-checked the move to Snowflake, it's time to start saying goodbye to your old Hadoop assets. Completing this step means gradually phasing out the old systems and data stores. Make sure you've cut all ties with the legacy setup and then redirect your resources to really make the most of what Snowflake has to offer.

Stages of migration process

Navigating the migration from Hadoop to Snowflake involves a clear-cut, three-step process: starting with the exploration phase, moving through the implementation phase, and finally reaching the validation phase. Let's take a closer look at what each of these stages entails for a seamless transition.

The Exploration phase

In the exploration phase, businesses need to collect essential background details about their current Hadoop environment and pinpointing all the important dependencies. You'll want to take stock of the different tools and technologies you're using, where your data's coming from, the use cases, the resources you have, how everything's integrated, and the service level agreements you're working with. 

If you're planning to migrate, you should:

  1. Conduct an inventory of diverse workload types operating within the cluster
  2. Develop and size a new architecture to accommodate both data and apps effectively
  3. Formulate a comprehensive migration strategy that minimizes disruptions

Information obtained in this stage will shape the ultimate migration strategy.

The Implementation phase

During the implementation phase, it's time for businesses to shift their business applications from Hadoop over to Snowflake. This is where you really put to use all the info you gathered in the discovery phase. You've got to pick out and prioritize which data sources, applications, and tools are up first for the move. Keep in mind, this stage is usually the longest and most technically challenging part of the whole project.

The Validation phase

The final step confirms the move from Hadoop to Snowflake was a success. Unlike traditional methods, such as A/B testing and running parallel systems, this phase can be significantly optimized using Datafold's advanced data diffing tools.

  1. Review and datafold integration: Start by reviewing your data models, categorizing them by business groups. Categorizing these models sets the stage for a structured, efficient migration. Integrate Datafold's Data Diff capabilities into your workflow to automate and streamline the validation process.
  2. Target setting and accountability: Assign business owners and data engineers to each business group, setting clear targets for accuracy. Encourage these teams to work collaboratively, leveraging Datafold to identify and explain any discrepancies in the data.
  3. Datafold's data diff workflow: Perform data diffs after each table refresh. Taking a systematic approach to data diffing helps comparing data tables fast and with confidence. Ensure high accuracy and surface any discrepancies through detailed analysis.
  4. Iterative process for accuracy: Using Datafold, iterate the data models until the desired level of correctness is achieved. Employing an iterative process, supported by Datafold's comprehensive diffing, allows for in-depth comparisons across rows, columns, and schemas, making it easy to identify and resolve discrepancies.
  5. Final acceptance and sign-off: Once the required accuracy level is reached and validated through Datafold, the business owner can formally approve the migration. Approval signifies that the data meets the agreed standards of correctness.
  6. Termination and transition: Following approval, data engineers can proceed to terminate access to the old data model in Hadoop, completing the transition to Snowflake. Terminating access prevents data drift and ensures that all operations are now fully aligned with Snowflake.

A data diffing-centric approach accelerates the validation process and enhances precision, accountability, and collaboration. The end result is more effective and reliable migration from Hadoop to Snowflake.

Ensuring a successful migration from Hadoop to Snowflake

Ultimately, the goal of this guide is to streamline your data migration process, making the shift from Hadoop to Snowflake as seamless as possible. As you set out on this path, keep in mind that the right tools and some expert advice can really make a big difference in streamlining the whole process. If you're on the lookout for some help to tackle your data migration challenges:

  • Reach out to our team of data migration specialists to discuss your specific migration needs, technical stack, and any concerns you have. We're here to assist you in determining if our solutions, like data diffing, are right for your situation.
  • For those eager to experience hands-on, our platform offers a free trial, allowing you to explore cross-database diffing capabilities right away. You can start integrating your databases today to see the benefits in action.

As emphasized at the start, migrations are complex and can extend over long periods. Our goal is to simplify and automate as much of this process as possible, enabling your team to concentrate on what's most important: maintaining and delivering high-quality data across your organization.