How ETL works in the Cloud

ETL (Extract, Transform, Load) has long been the go-to approach for data teams that need to gather vast amounts of data from multiple sources and prepare it for analysis. However, with the rise of cloud computing, a new paradigm called Cloud ETL has emerged. This has completely revolutionized the way organizations manage their data transformation and handle their data integration processes.

Cloud ETL, in contrast to ETL, harnesses the power of cloud computing technologies to perform the extraction, transformation, and loading of data. By leveraging the scalability, flexibility, and cost-effectiveness of the cloud, organizations can massively enhance and streamline their ETL operations.

In this article, we will delve into the world of Cloud ETL, exploring its benefits, features, and use cases. We will discuss how Cloud ETL enables organizations to handle large volumes of data, integrate diverse data sources, and accelerate the data preparation process.

What is cloud ETL?

Cloud ETL is a data integration process that leverages cloud computing technologies and resources to perform the extraction, transformation, and loading of data from various sources into a target system, such as a data warehouse or a data lake. It involves utilizing cloud-based services, platforms, and infrastructure to facilitate the seamless and scalable movement of data across different environments, ensuring its quality, consistency, and accessibility for analytical purposes. Cloud ETL encompasses the following key components:

  1. Extraction: Data is extracted from diverse sources, which may include databases, files, APIs, web services, or streaming platforms. Cloud ETL solutions provide connectors and tools that enable efficient data extraction, whether from on-premises systems or cloud-based sources.
  2. Transformation: Extracted data undergoes a series of transformations to cleanse, enrich, aggregate, or reshape it according to specific business requirements. Cloud ETL platforms offer a range of transformation capabilities, such as data mapping, filtering, data type conversion, data validation, and integration with external data processing frameworks. Transformations can be written in SQL, Python or Scala.
    Learn how RudderStack transforms real-time data using Transformations which enable you to write simple code based functions using Javascript or Python.
  3. Loading: Transformed data is loaded into a target system, such as a cloud data warehouse, data lake, or analytical platform. Cloud ETL enables organizations to efficiently handle large volumes of data by leveraging scalable cloud infrastructure and parallel processing techniques. It ensures the data is securely and optimally stored, ready for downstream analytics, reporting, or machine learning tasks.

Traditional ETL vs. Cloud ETL

Traditional ETL requires businesses to invest in expensive hardware and software, as well as hire a team of IT professionals to manage the process. However, cloud ETL is a service-based solution that eliminates the need for hardware investments. In addition, it offers greater scalability and flexibility than traditional ETL. With cloud ETL, businesses can easily scale up or down the amount of data they process according to their needs. This feature makes it an attractive solution for businesses that experience fluctuating workloads.

Another advantage of cloud ETL is that it allows organizations to easily integrate data from various sources, including cloud applications and APIs, then apply a series of transformations with automated data pipelines. This is particularly important in today's interconnected business environment, where companies can change and rely on a variety of applications and services to run their operations. Cloud ETL makes it easy for businesses to extract data from these sources and make it available for analytics and business intelligence.

Advantages of Cloud ETL

Cloud ETL is a powerful data management solution that allows organizations to efficiently manage large volumes of data from various sources. With its scalability, flexibility, and affordability, cloud ETL is an attractive option for businesses looking to gain valuable insights and make informed decisions. Some of the key benefits that cloud ETL has for data management are:

  1. Scalability and flexibility: Cloud ETL leverages the scalability of cloud infrastructure, allowing organizations to handle large volumes of data and accommodate fluctuating workload demands. Cloud platforms provide the ability to scale up or down resources based on data processing needs, ensuring optimal performance and cost-efficiency.
    For example, a retail company may experience a spike in sales during the holiday season. With cloud ETL, the company can easily scale up its data processing needs to handle the increased volume of sales data. Once the holiday season is over, the company can scale back down its data processing needs, saving on costs.
  2. Cost efficiency: Cloud ETL offers cost advantages by eliminating the need for upfront infrastructure investments. Organizations can leverage pay-as-you-go models, where they only pay for the resources consumed during the ETL process. Additionally, cloud platforms provide opportunities for cost optimization through auto-scaling, resource utilization monitoring, and fine-grained control over compute and storage resources.
    For example, a startup company with limited resources can benefit from cloud ETL. The company can use cloud resources to process its data without investing in expensive hardware or hiring a large IT team. This can help the company save on costs and focus on growing its business.
  3. Enhanced data security: Cloud providers invest heavily in security measures and compliance certifications, making them a reliable choice for handling sensitive data. Cloud ETL solutions offer encryption, access controls, data governance features, and compliance frameworks to ensure data security and regulatory compliance.
    For example, a healthcare company that handles sensitive patient information can benefit from cloud ETL. The company can use cloud resources to process its data while ensuring that patient information is kept secure and compliant with regulation, by using the built in integrations with cloud Identity providers that offer granular role based access controls and multi-factor authentication.
  4. Improved data integration and collaboration: Collaboration on data projects may get complex, but Cloud ETL facilitates seamless data integration and collaboration across multiple teams. With cloud ETL, departments and teams can easily share data in real-time, which can improve overall efficiency. Cloud ETL allows businesses to make data-driven decisions based on accurate data analytics and insights, which can improve productivity and revenue.

For example, a marketing team can use cloud ETL to integrate customer data from various sources, such as social media and email campaigns. The team can then analyze the data to gain insights into customer behavior and preferences, which can inform marketing strategies and improve customer engagement.

Choosing the right Cloud-based ETL tool

There are several popular cloud ETL tools available in the market ranging from proprietary SaaS to open-source tools that can be deployed in cloud environments. Each offers their own unique features and capabilities. Here are a few examples of widely used cloud ETL tools:

  1. Amazon Web Services (AWS) Glue: AWS Glue is a fully managed ETL service provided by Amazon Web Services. It offers features like data cataloging, automated schema inference, and data transformation capabilities. It integrates well with other AWS services such as Amazon S3, Amazon Redshift, and Amazon Athena, making it a popular choice among organizations using AWS.
  2. Google Cloud Dataflow: Google Cloud Dataflow is a serverless data processing service that offers ETL capabilities. It enables organizations to build scalable data pipelines using Apache Beam, a unified programming model for batch and streaming data processing. Dataflow integrates well with other Google Cloud services such as Google BigQuery and Google Cloud Storage.
  3. Microsoft Azure Data Factory: Azure Data Factory is a cloud-based data integration service provided by Microsoft Azure. It enables organizations to create and manage data-driven workflows for orchestrating data movement and transformation. Azure Data Factory integrates with various data sources and supports hybrid scenarios, allowing seamless integration between on-premises and cloud-based systems.
  4. RudderStack Cloud Extract: With RudderStack Cloud Extract, you can collect your raw events and data from different cloud tools such as Facebook Ads, Google Analytics, Marketo, HubSpot, Stripe, and more. You can then build efficient ELT pipelines from these cloud apps to your data warehouse.
  5. Talend Cloud: Talend Cloud is a unified integration platform that includes ETL capabilities. It offers a visual interface for designing data integration workflows and supports a wide range of data sources and destinations.
  6. Informatica Cloud: Informatica Cloud is a comprehensive cloud integration platform that offers ETL capabilities. It provides a range of connectors, data transformation features, and data quality management capabilities. Informatica Cloud supports integration with on-premises systems, cloud applications, and data lakes, making it suitable for organizations with datasets from diverse data sources.
  7. Apache NiFi: Apache NiFi is a powerful data integration and processing tool that supports ETL workflows. It provides a web-based user interface for designing and managing data flows, allowing users to easily connect different data sources and perform transformations. NiFi is highly scalable, fault-tolerant, and offers extensive data routing capabilities.

Today, many cloud vendors provide ETL tooling, adding to the array of options available to businesses. When evaluating cloud ETL tools from different vendors, there are several additional aspects to consider:

  1. Connectivity and data source support: Consider the tool's connectivity options and its ability to connect to various data sources relevant to your business, including on-premise databases, cloud-based systems, files, APIs, and streaming platforms. Ensure that the tool provides the necessary connectors, adapters, or APIs for seamless integration with your specific data sources.
  2. Ease of use and user interface: Consider the usability and intuitiveness of the tool's user interface. A user-friendly interface simplifies the process of designing and managing ETL workflows, reducing the learning curve for users. Look for features like drag-and-drop, no-code or low code functionality, visual data mapping, and intuitive workflow design capabilities.
  3. Integration and compatibility: Evaluate how well the cloud ETL tool integrates with other systems and tools that your business relies on, such as data warehouses, business intelligence platforms, or analytics tools. Compatibility with your existing infrastructure and technology stack is crucial to ensure smooth data flow and interoperability.
  4. Cost and pricing model: Consider the pricing model of the cloud ETL tool, whether it is based on usage, subscription, or a combination. Evaluate the total cost of ownership, including any additional costs for data transfer, storage, or compute resources. Choose a tool that aligns with your budget and provides transparent pricing structures.
  5. Security and compliance: Ensure that the cloud ETL tool provides robust security measures to protect your data during extraction, transformation, and loading. Look for features like data encryption, role-based access controls, and compliance certifications (e.g., GDPR, HIPAA) to meet your industry-specific security and regulatory requirements.
  6. Vendor support and roadmap: Consider the level of support provided by the tool vendor, including documentation, training resources, and access to technical support. Evaluate the vendor's commitment to product updates, bug fixes, and feature enhancements through a clear roadmap. Engage with the vendor to understand their responsiveness to customer feedback and their dedication to addressing customer needs.

By carefully evaluating these aspects when considering cloud ETL tools from different vendors, businesses can choose a solution that best aligns with their requirements, leverages the capabilities of the chosen cloud provider, and enables seamless data integration and management in the cloud environment.


Cloud-based ETL (Extract, Transform, Load) has emerged as a transformative solution for organizations seeking efficient and scalable data integration processes as a result of the big data boom. By harnessing the capabilities of cloud platforms, businesses can effectively manage their data, extract valuable insights, and gain a competitive edge in today's data-driven landscape.

When choosing a cloud ETL tool, businesses should consider a number of factors, such as cloud vendor ecosystem, scalability, connectivity, data transformation capabilities, ease of use, integration possibilities, security, cost, and vendor support. Evaluating these aspects ensures the selection of a tool that aligns with specific business requirements and optimizes the data integration process.

Get the Data Maturity Guide

Our comprehensive, 80-page Data Maturity Guide will help you build on your existing tools and take the next step on your journey.

Build a data pipeline in less than 5 minutes

Create an account

See RudderStack in action

Get a personalized demo

Collaborate with our community of data engineers

Join Slack Community