Amazon’s consumer business completed its years-long migration off of Oracle databases, beating its self-imposed deadline. The move saved Amazon money and improved application performance, said Jeff Barr, chief evangelist for Amazon Web Services (AWS), in a blog post.

The tech giant migrated 75 petabytes of data in about 7,500 Oracle databases to multiple AWS database services including Amazon DynamoDB, Amazon Aurora, Amazon Relational Database Service (RDS), and Amazon Redshift. Barr said the team completed the migrations with “little or no downtime, and covered 100% of our proprietary systems” including purchasing, catalog management, order fulfillment, accounting, and video streaming.

By turning off Oracle, Amazon cut its database costs by more than 60%, Barr said, adding that customers “regularly report” cost savings as high as 90% by moving from Oracle to AWS. It also reduced latency of its consumer-facing applications by 40%, and reduced database admin overhead by 70%, according to the blog.

“The migration gave each internal team the freedom to choose the purpose-built AWS database service that best fit their needs, and also gave them better control over their budget and their cost model,” Barr wrote.

AWS migrated low-latency services to DynamoDB and highly scalable non-relational databases such as Amazon ElastiCache. Meanwhile transactional relational workloads with high data consistency requirements moved to Aurora and RDS, while analytics workloads switched to AWS’ Redshift cloud data warehouse.

Oracle co-founder and CTO Larry Ellison has a long-running and well-documented feud with Amazon, and he likes to boast about how AWS’ business runs on Oracle’s databases. “A company you’ve heard of just gave us another $50 million this quarter to buy Oracle database and other Oracle technology. That company is Amazon,” Ellison said on an earnings call last year.

Shortly after, however, reports surfaced that Amazon planned to move entirely off Oracle databases by the first quarter of 2020. AWS beat that deadline, however, and after they turned off the final Oracle database, the team popped the champagne.