Saturday June 7 was the 25th anniversary of DB2. Ingres and Oracle preceded it as commercial products by a narrow margin, but the launch of DB2 on June 7, 1983, marked the birth of relational database as a cornerstone for the enterprise.

DB2 came about as a result of an unprecedented collaboration between academic and commercial database researchers. Both took Edgar Codd's elegant theoretical concept and built examples of a flexible system, capable of serving data to thousands of users at a time, based on it. Relational database was the opposite of everything that had gone before in data storage.

"You could dynamically add tables or change tables without taking the system down. It doesn't take much imagination now to see this was a huge leap forward," recalled Don Haderle, chief architect of DB2, referred to within IBM ranks as the father of DB2.

At first, relational database was a highly mocked product, halting in its performance compared to the programmed-path systems. Skeptics like John Cullinane, founder of Cullinet Software, once took this reporter aside to instruct him that relational database would never amount to anything compared to his firm's IDMS product. Last year, relational database represented an $18.6 billion a year market, according to IDC. Ecommerce would be impossible without it.

Researchers at IBM's Santa Theresa Lab in San Jose were frequently drawn from the ranks of early computer science students at the nearby University of California at Berkeley, where Bob Epstein, Jerry Held, Jim Gray, Michael Stonebraker and others made such rapid progress on the experimental Ingres system that it put pressure on Big Blue to productize its own invention.

Predecessor systems like IBM's IMS and VSAM on the mainframe could store megabytes of data, but it had to be entered and retrieved in the same structured way every time. Changing the structure or sequence of data meant taking the database offline, with programmers laboring over it for hours to make sure the changes didn't torpedo the handful of systems that depended on the storage mechanism. With relational database, dozens or hundreds of applications can be added to the same system, each getting the data it needs in the desired format.

Initially, however, relational database was the subject of serious experimentation at Berkeley, not product development. IBM researcher Edgar Codd had written a series of papers in the 1960s and 1970s proposing a new kind of database. Codd died in April 2003, but his former associates told The New York Times for his obituary: "His approach was not, shall we say, welcomed with open arms at IBM. It was a revolutionary approach," said Harwood Kolsky, a physicist who had worked with Codd.

Don Haderle, project lead for the IBM DB2 team, now retired, confirmed in a recent interview some internal opposition. DB2 development was not funded through the existing IMS and mainframe software group, which opposed it. "IMS had been developed for McDonnell Douglas by a field development group [closely aligned with sales], not by research," recalled Haderle in a recent interview. McDonnell Douglas had asked for a system to manage its inventory of parts and IBM field engineers produced IMS, noted Haderle.

The IBM storage organization, realizing that every IMS customer tended to increase by a hundredfold the amount of storage it bought, agreed to fund the DB2 project. It was a long shot, but just maybe the pointy headed researchers would produce another product that increased storage sales, Haderle recalled.