The shift to open source database software is reportedly weakening Oracle and other traditional database vendors as major customers like Amazon ready lowest cost alternatives.

Oracle (NYSE: ORCL), which implemented a cloud computing initiative last year, insisted in December that large database customers such as Amazon and Salesforce remain among its roster of Fortune 500 database customers. Since then, reports have emerged that Amazon and other large customers are moving away from Oracle as they roll out open-source alternatives.

The web site The Information reported this week that several sources insisted Amazon and Salesforce are preparing to move off of Oracle databases. Oracle officials insist otherwise.

Indeed, Amazon Web Services has recently unveiled a raft of database options based on open source software. Among them is a new graph database. Dubbed Nepture, the graph database complements a growing list of AWS platforms, including relational, No,SQL and in-memory databases along with key-value and object stores.

CEO Andy Jassy noted during and AWS event in November that emerging platforms like Neptune would help fill gaps in how developers access data. In a not-so-veiled dig at Oracle, Jassy added: “The landscape of how people use databases today is really different than what’s been the case over the last number of years,” he said. “You don’t use relational databases for every application. That ship has sailed.”

Industry watchers note that shifting databases is difficult since they often support a range of enterprise software applications. However, The Information report notes there is ample incentive to make the transition given Oracle’s aggressive enforcement of database licensing agreements.

Another incentive for hyper-scalers like AWS to roll out open source database alternatives is the difficulty of scaling current platforms. The report quoted a former Amazon employee who asserted that early AWS database efforts were prompted by e-commerce outages that spurred efforts to move away from monolithic relational databases to more agile, open-source alternatives.

Many of those efforts were unveiled by AWS during the cloud giant’s annual technology event in November. Precisely how those database technologies would be integrated into Amazon’s internal operations remains to be seen.

Amazon did not respond to a request for comment on the database report.

Those reports are emerging as AWS and Oracle lock horns in the growing effort to move database resources to the cloud. During a Dec. 14 earnings call, Oracle CTO Larry Ellison went out of his way to challenge Amazon’s database strategy, announcing what he referred to as the world’s first “self-driving database.”

“The new artificially intelligent Oracle database is fully automated and requires no human labor for administration” Ellison asserted. “If a security vulnerability is detected, the database immediately patches itself while running.”

Added Ellison” “The price of running the Oracle Autonomous Database in the Oracle Cloud is less than half the cost of running a database in the Amazon Cloud.”

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