There's been a lot of chest thumping of late by SAP and Oracle regarding their fledgling in-memory products, Hana and Exalytics.

SAP has been confidently claiming that its Hana in-memory database will quickly steal database market share that it took Oracle decades to win. It will start with SAP Business Warehouse (BW) deployments, the company says, and by the end of this year, once Hana gains the ability to run core enterprise applications, Hana will start invading the transactional database market.

Oracle's Larry Ellison and Safra Catz have missed few opportunities to discredit Hana in recent months. But executive VP Thomas Kurian took the slams a level deeper on Friday with a one-hour Webinar clearly intended to sow seeds of fear, uncertainty and doubt in the minds of would-be Hana customers. The session was billed as an Exalytics seminar, but each point set up a contrast with Hana. Kurian claimed, among other things, that SAP's product costs five times to 50 times more than Exalytics and that it doesn't support SQL (relational) or MDX (multidimensional) query languages, requiring apps to be rewritten to run on the new database.

[ Want more on SAP's latest moves? Read SAP Launches Attack On Database, Mobile App Markets. ]

So what's the truth behind all these claims and counter claims? SAP database executive Steve Lucas posted a blog on Monday rebutting most of Oracle's claims, and also I spent some time with SAP's CTO, Vishal Sikka, and Gartner analyst Don Feinberg on some of the technical points, as I'll detail below. But first a bit of background.

SAP has always said customers will be free to choose whatever database they want, but the company is counting on Hana's in-memory performance to catapult it to a leading position in the database market. The advantages of in-memory technology are well documented, but SAP has bigger ambitions for the technology than any other vendor. With Hana, the goal is to support "transformational" business advantage, not just faster queries.

Gas and electric utility Centrica, for example, uses a Hana-based app to capture and analyze the massive amount of data generated by smart meters. With real-time analysis of usage as frequently as every 15 minutes (rather than just monthly totals), Centrica has a clearer understanding of usage by neighborhood, the size of the homes or businesses, building types and other dimensions.

Centrica also can exploit Hana's performance to interact with customers in new ways. The utility can change consumption patterns by, for example, creating tailored discounts to encourage specific customers (particularly big commercial customers) to shift their energy consumption to off-peak hours. Efficiency programs can target specific customers segments identified though fine-grained analysis. And to help customers help themselves, the utility can give customers insight into their energy usage patterns with online and mobile tools that track changes in real time, so they can see their energy loads in specific operating modes. That's not something you can achieved with daily batch updates into a conventional data warehouse.

SAP now has nearly a dozen of these new applications designed specifically for Hana, including sales and operations planning, cash and liquidity management, and, for retail, trade-promotion management and merchandising and assortment management. SAP has couple dozen more apps in development. In some cases apps fitting these descriptions already existed, but they've been redesigned to take advantage of what SAP calls "real, real-time" -- meaning you can take action based one what's happening now, not what happened yesterday or a few hours or even minutes ago.

SAP's hype about these apps is getting a little ahead of deployed market reality. Both Hana and Oracle Exalytics can point to dramatic before-and-after differences in query speeds. (Even SAP grants that Exalytics can accelerate queries.) SAP says the real payoff from Hana will be in transforming business processes, not just accelerating queries. But we haven't seen enough solid, real-world customer examples documenting transformed business competitiveness.

SAP recently offered a handful of customer examples, including Centrica (mentioned above), Aqualectra (another utility), Medidata (a SaaS-based service firm that helps big pharmaceutical companies run clinical trials), and an unnamed Japanese retailer. But the summary stories were loaded with platitudes like, "Hana helps us bring our customers new efficiencies that they never even dreamed of." Okay, like what? If I'm spending big bucks, I want rich details about tangible competitive advantage. Hana became generally available last summer, and early ramp-up customers were quoted at SAP's Sapphire event last year. So it's time to start hearing about the detailed case examples and testimonials. I'm hoping that happens at Sapphire later this month.