Delta Lake is a powerful storage layer that enables scalable, reliable, and performant data pipelines on top of Apache Spark. In the previous article, we discussed INSERT OVERWRITE vs INSERT INTO for Efficient Table Insertion
One of the key features of Delta Lake is the ability to perform atomic, scalable, and high-performance updates and merges of data through its Merge and Copy Into commands. In this article, we will explore these two commands and their performance implications on Delta Tables.
Merge Command
The Merge command allows you to merge data from one table or data frame into another table based on a join condition. The Merge command supports three types of operations: insert, update, and delete.
Here is an example of a Merge command that updates a Delta Table called sales with new data from another Delta Table called new_sales: