Oracle has agreed to buy privately held TimesTen for an undisclosed sum.

TimesTen develops real-time data management software, a database that resides in the application tier. The tool offers data caching for applications that must be instantly responsive, highly scalable and require continuous availability.

The software category caters to applications including call processing for telecoms providers, real-time billing, stock trading, call centres and airline operations.

The TimesTen database holds only a small subset of the data, with the total dataset being stored in a larger database such as that developed by Oracle. TimesTen chief executive Jim Groff said that the two products are complementary rather than competing.

Andrew Mendelsohn, senior vice president for Oracle Database Server Technologies, added: "This will enable us to provide our customers with instantly responsive and continuously available access to critical transaction data."

The TimesTen caching product already offers out-of-the-box integration with the Oracle database and about half of the current customers use it with Oracle's software. Users of other databases, including IBM's DB2, have to create custom code to accomplish integration.

Oracle plans to keep selling the product on an individual basis, but will also increase the integration with its database.

The software is generating interest from prospective buyers due to developments in the financial industry, defence and the advent of 3G wireless networks. Users also increasingly use the software with regular enterprise applications, according to Groff.

Oracle has scheduled a webcast on 21 June to inform users about the acquisition. 

TimesTen is headquartered in Mountain View, California and has 90 employees, of whom Oracle plans to retain the vast majority.