What Is Delta Lake?
Delta Lake is an open-source storage layer that maintains the foundation for keeping and managing data. It provides a transactional storage layer that enables data engineers and data scientists to perform complex data operations, such as inserts and deletes, on large-scale data lake storage. With Delta Lake, data engineers and data scientists can perform these operations without the need to move data to a separate storage layer, which can save time, reduce complexity and improve performance.
Delta Lake also provides a mechanism for data versioning, which allows users to store different versions of the same data, and track changes to the data over time. This allows users to easily roll back to a previous version if necessary and enables time travel to query the data as it existed at a specific time. This can be useful for auditing, compliance, and reproducibility of data science experiments. Delta Lake also provides built-in support for data lineage and change data capture, which enables users to track the lineage of data and how it has been transformed over time.
How Does Delta Lake Work?
Delta Lake works by providing a transactional storage layer on top of existing data lakes, enabling data engineers and scientists to perform ACID transactions and data versioning on a bigger data lake. It allows data engineers and scientists to perform complex data operations on large-scale data lake storage without the need to move data to a separate storage layer. Delta Lake stores the data in a Parquet format, a columnar storage format, which enables it to perform operations like filtering, aggregation, and compression more efficiently. Delta lakes provide mechanisms for data versioning and time travel and also uses a transaction log to keep track of the changes made to the data.
Benefits of Delta Lake
ACID Transactions
Delta Lake enables ACID transactions, which stands for Atomicity, Consistency, Isolation, and Durability. This allows for data integrity and consistency even in a distributed environment where multiple users are interacting with the data at the same time. It also allows for performing complex data operations like upserts and deletes on large-scale data lake storage, which traditional data lake cannot handle.
Data Versioning and Time-Travel
Delta Lake provides a mechanism for data versioning, which allows users to store different versions of the same data, and track changes to the data over time. This allows users to easily roll back to a previous version if necessary and also enables time travel, the ability to query the data as it existed at a specific point in time. This can be useful for auditing, compliance, and reproducibility of data science experiments.
Data Lineage and Change Data Capture
Delta Lake also provides built-in support for data lineage and change data capture, which enables users to track the lineage of data and how it has been transformed over time. This allows for understanding the data flow and lineage, which can be useful for auditing, compliance, and troubleshooting.
Performance and Scalability
Delta Lake uses a columnar storage format, Parquet, which enables it to efficiently perform operations like filtering, aggregation, and compression, leading to faster query performance. Additionally, it is built on top of existing data lakes which allows it to leverage the scalability of data lakes. This allows for handling large amounts of data and handling growing data needs.
Open-Source
Delta Lake is an open-source technology, which means that it is free to use and can be easily integrated with other open-source big data technologies like Apache Spark and Apache Hive.
Use Cases
Data Quality Management
Delta Lake can be used to improve data quality management for data lakes. Data quality issues such as missing, duplicate, or inconsistent data can be identified and corrected using Delta Lake's ACID transactions, data versioning, and time-travel features. This makes for a clean and consistent data set, which can improve the accuracy of data analysis and decision-making.
Data Governance
Delta Lake's data lineage and change data capture features can be used for data governance, to ensure that the data is compliant with regulations and internal policies.
Data Science and Machine Learning
Delta Lake can be used in conjunction with big data processing and analytics platforms to enable data scientists and machine learning engineers to perform advanced analytics on large-scale data.
