Data Lake vs Data Warehouse

GUPTA, Gagan       Posted by GUPTA, Gagan
      Published: June 6, 2021

Enjoy listening to this Blog while you are working with something else !


What is Data Lake

A data lake is a centralized repository that allows you to store all your structured and unstructured data at any scale. You can store your data as-is, without having to first structure the data, and run different types of analytics-from dashboards and visualizations to big data processing, real-time analytics, and machine learning to guide better decisions.

Data Lakes compared to Data Warehouses - two different approaches

Depending on the requirements, a typical organization will require both a data warehouse and a data lake as they serve different needs, and use cases.

A data warehouse is a database optimized to analyze relational data coming from transactional systems and line of business applications. The data structure, and schema are defined in advance to optimize for fast SQL queries, where the results are typically used for operational reporting and analysis. Data is cleaned, enriched, and transformed so it can act as the 'single source of truth' that users can trust.

A data lake is different, because it stores relational data from line of business applications, and non-relational data from mobile apps, IoT devices, and social media. The structure of the data or schema is not defined when data is captured. This means you can store all of your data without careful design or the need to know what questions you might need answers for in the future. Different types of analytics on your data like SQL queries, big data analytics, full text search, real-time analytics, and machine learning can be used to uncover insights.

As organizations with data warehouses see the benefits of data lakes, they are evolving their warehouse to include data lakes, and enable diverse query capabilities, data science use-cases, and advanced capabilities for discovering new information models. Gartner names this evolution the 'Data Management Solution for Analytics' or 'DMSA.'

Our On-Premise Corporate Classroom Training is designed for your immediate training needs
Data Lake vs Data Warehouse
Data Lake vs Data Warehouse

Comparison of Data Lake and Data Warehouse

Characteristics Data Warehouse Data Lake
Data Relational from transactional systems, operational databases, and line of business applications Non-relational and relational from IoT devices, web sites, mobile apps, social media, and corporate applications
Schema Designed prior to the DW implementation (schema-on-write) Written at the time of analysis (schema-on-read)
Price/Performance Fastest query results using higher cost storage Query results getting faster using low-cost storage
Data Quality
Highly curated data that serves as the central version of the truth Any data that may or may not be curated (ie. raw data)
Users Business analysts Data scientists, Data developers, and Business analysts (using curated data)
Analytics Batch reporting, BI and visualizations Machine Learning, Predictive analytics, data discovery and profiling

Our On-Premise Corporate Classroom Training is designed for your immediate training needs

The essential elements of a Data Lake and Analytics solution

As organizations are building Data Lakes and an Analytics platform, they need to consider a number of key capabilities including:

Data movement

Data Lakes allow you to import any amount of data that can come in real-time. Data is collected from multiple sources, and moved into the data lake in its original format. This process allows you to scale to data of any size, while saving time of defining data structures, schema, and transformations.

Securely store, and catalog data

Data Lakes allow you to store relational data like operational databases and data from line of business applications, and non-relational data like mobile apps, IoT devices, and social media. They also give you the ability to understand what data is in the lake through crawling, cataloging, and indexing of data. Finally, data must be secured to ensure your data assets are protected.


Data Lakes allow various roles in your organization like data scientists, data developers, and business analysts to access data with their choice of analytic tools and frameworks. This includes open source frameworks such as Apache Hadoop, Presto, and Apache Spark, and commercial offerings from data warehouse and business intelligence vendors. Data Lakes allow you to run analytics without the need to move your data to a separate analytics system.

Machine Learning

Data Lakes will allow organizations to generate different types of insights including reporting on historical data, and doing machine learning where models are built to forecast likely outcomes, and suggest a range of prescribed actions to achieve the optimal result.

The value of a Data Lake

The ability to harness more data, from more sources, in less time, and empowering users to collaborate and analyze data in different ways leads to better, faster decision making. Examples where Data Lakes have added value include:

Improved customer interactions

A Data Lake can combine customer data from a CRM platform with social media analytics, a marketing platform that includes buying history, and incident tickets to empower the business to understand the most profitable customer cohort, the cause of customer churn, and the promotions or rewards that will increase loyalty.

Improve R&D innovation choices

A data lake can help your R&D teams test their hypothesis, refine assumptions, and assess results-such as choosing the right materials in your product design resulting in faster performance, doing genomic research leading to more effective medication, or understanding the willingness of customers to pay for different attributes.

Increase operational efficiencies

The Internet of Things (IoT) introduces more ways to collect data on processes like manufacturing, with real-time data coming from internet connected devices. A data lake makes it easy to store, and run analytics on machine-generated IoT data to discover ways to reduce operational costs, and increase quality.  

The challenges of Data Lakes

The main challenge with a data lake architecture is that raw data is stored with no oversight of the contents. For a data lake to make data usable, it needs to have defined mechanisms to catalog, and secure data. Without these elements, data cannot be found, or trusted resulting in a 'data swamp." Meeting the needs of wider audiences require data lakes to have governance, semantic consistency, and access controls.


Support our effort by subscribing to our youtube channel. Update yourself with our latest video`s on Data Science.

Looking forward to see you soon, till then Keep Learning !

Our On-Premise Corporate Classroom Training is designed for your immediate training needs
Data Lake vs Data Warehouse

Corporate Scholarship Career Courses