At 04:23 PM 2/13/2004, Aage Johansen wrote:

>Someone posted this on borland.public.interbase.general today:

Ziemowit wrote:

Is Interbase a further development, port or just a case of
reverse-engineering of Digital's RDB in some version?

Interesting question and the answer is none of the above. Borland got
InterBase when they bought Ashton-Tate in 1991. Ashton-Tate bought got
InterBase when
they bought Interbase Software Corporation that same year. The three
founders of Interbase Software Corporation, Jim Starkey, Don DePalma, and
I, worked
together at DEC where Jim was the principal designer of DSRI - the Digital
[Equipment Corporation] Standard Relational Interface. The interface
definition was
very detailed and specific because two groups were building relational
databases at DEC - the Rdb/VMS group and the renegades. Jim was
Renegade-In-Chief.
Don wrote the DSRI Reference Manual. I tried to keep the two groups from
committing mayhem on each other, not successfully, so DEC hired a gentleman
by the
name of David Hartzband to be the "architect" for the process. Dr.
Hartzband's qualifications include a doctorate in Philosophy from
Heidelberg, a degree in
computer science from CMU, and some years spent as a bouncer at the Buckets
of Blood bar outside the Pittsburgh steel mill gates.

The two products had exactly identical interfaces - right down to the error
codes. Change a logical name, and your program ran against one database or
the other -
no code changes, no recompile, no relink. Made performance comparisons
simple - and the competition make them effective. At the time (early
80's) it was
understood that for performance you needed a CODASYL database. Pitting
Rdb/VMS and Rdb/ELN against each other made everybody get over that idea -
generally we got a factor of 10 performance gain every three months.

The principal differences between Rdb/VMS and Rdb/ELN were that the former
was created by the Commercial Languages Database group and the latter used
multi-versioning concurrency control. MVCC was much too radical for DEC
management (especially Commercial Languages) at that point. A process was
established for determining which database would be the official DEC
product, but that process took longer than developing and releasing the
databases. The
renegade group quit and founded InterBase software.

InterBase was a new implementation of the published DSRI specification -
completely legal and above board. The DEC products were written in BLISS,
InterBase
in C. It too was plug-compatible with Rdb/VMS and Rdb/ELN.

Cheers,


Ann