By the end of this year, almost all of Amazon's databases that ran on Oracle will be on an Amazon database instead, Amazon Web Services CEO Andy Jassy said.

"We're virtually done moving away from Oracle on the database side," Jassy told CNBC's Jon Fortt in an interview that aired Wednesday. "And I think by the end of 2019 or mid-2019 we'll be done."

Amazon is reducing its reliance on Oracle for its data needs and is instead using its own services. Jassy said 88 percent of Amazon databases that were running on Oracle will be on Amazon DynamoDB or Amazon Aurora by January. He added that 97 percent of "mission critical databases" will run on DynamoDB or Aurora by the end of the year. On Nov. 1, Amazon moved its data warehouse from Oracle to its own service, Redshift, Jassy said.

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