What is data lake?
A data lake is a storage repository that stores data in its raw format, without any predefined structure or schema. Here are some of the key characteristics, architecture, and components of a data lake:
Stores all types of data, including structured, semi-structured, and unstructured data
Designed to be highly scalable and cost-effective
Supports various data sources, both internal and external
Offers fast and easy data access for analysis and processing
Provides a flexible schema-on-read approach for data querying and analysis
Data lake architecture is based on a distributed file system, such as Hadoop Distributed File System (HDFS), Amazon Simple Storage Service (S3), or Azure data lake Storage (ADLS).
Data lakes are built on top of cloud-based infrastructure and use cloud-based storage solutions, making them highly scalable and cost-effective.
The architecture also includes data ingestion tools that can handle different data formats and sources, data processing tools for cleaning, transforming, and enriching data, and data analytics tools for querying and analyzing data.
Data ingestion tools enable the ingestion of data from various sources, including batch processing and real-time streaming data.
Data processing tools are used to clean, transform, and enrich data for analysis and querying.
Data storage is the central component of the data lake architecture, and it stores all data in its raw format.
Data analytics tools enable users to query and analyze data using various tools, including SQL queries and machine learning algorithms.
Data governance tools provide visibility and control over data access, quality, and security.
What is data mart?
A data mart is a subset of an enterprise’s data warehouse, which stores business data from a specific business unit or department. Its primary function is to provide fast and easy access to data for business users, analysts, and data scientists. Unlike data lakes, marts are built on a relational database, and their structure is optimized for the specific needs of the business function they serve.
The components of a data mart include data sources, extract-transform-load (ETL) processes, data storage, and access tools. Data marts only hold summarized data, with less emphasis on storing raw data or integrating data from external sources. Dependent data marts rely on an existing data warehouse, while independent data marts can stand alone.
The architecture of a data mart is different from a data warehouse. It is built as an independent data repository that is tailored to meet the specific needs of a business unit.
Read more about data mart and their use cases — What is a Data Mart? Key Concepts and Advantages
Why is it important to know the difference between data lake and data mart?
Ignoring the key differences between a data lake and a data mart can lead to serious consequences for a business. For instance, if a business fails to differentiate between the two and uses them interchangeably, it can affect the quality and consistency of the data. Raw data, which is typically stored in a data lake, can become polluted with inaccurate or irrelevant data, affecting data analysis and insights.
Note that data marts store structured data that has already been processed for specific business purposes. They also provide enhanced data analytics and insights by storing summarized and processed data sets that can be accessed quickly and easily by business users.
Understanding the key difference between a data lake and a mart is crucial for improved data quality and consistency. Data Scientists and data engineers can leverage data lakes to store raw data from different data sources, process data, and perform data integration. This data can then be analyzed to reveal insights and patterns that inform business decisions.
In terms of operational efficiency and cost savings, data lakes and marts serve different purposes. Data lakes, for example, are ideal for storing and processing large volumes of raw data, while the latter is designed to store specific sets of data for particular business functions. By utilizing the right technology, such as a cloud-based Data Warehouse, businesses can take advantage of both approaches, reducing operational costs and improving efficiency.
Key differences between data lakes and data marts everyone should know of