For some years now the distinction between various types of computers - large mainframes, intermediate-size minis, and small micros - has become increasingly blurred.
An example of just how far this process has gone is a recent announcement by Oracle. This five-year-old software company has made its reputation by commercially pioneering one of the most sophisticated types of software in the mainframe world, a filing program called a relational data base. At a conference of users this week, Oracle's president, Larry Ellison, announced the firm has squeezed its giant program onto the IBM Personal Computer and several work-alikes.
''This is not a subset of Oracle, not a cut-down version, but a fully functional version that looks and performs exactly like Oracle operating on IBM's $20 million premier machine,'' Mr. Ellison says.
Oracle has an installed base of over 800 systems on mini and mainframe computers. The company prices its program at $96,000 on mainframes and $24,000 on minis. The micro version will sell for $1,000 a copy.
A filing or data-base program like Oracle's is one of the fundamental types of software running on business computers. They form the basis for everything from mailing lists to accounting systems. The simplest form of data-base program is analogous to an index card file, storing information in a sequence of electronic records. Relational data bases like Oracle's are more complicated. They organize information in tables with rows and columns linked in various ways. Relational data bases are popular for their greater efficiency and flexibility.
According to Ellison, Oracle's new micro version will help reduce the severe communication problems that exist between the new micros and their big brothers. Personal computers have evolved languages which are incompatible with those on larger computers. As the small computers have infiltrated large companies, the result has been a computer version of the Tower of Babel. Managers with computers on their desks haven't been able to tap information directly from the company's main data banks.
For companies running Oracle, that need no longer be the case, Ellison says. Subject to the system's security provisions, a manager with an IBM PC and the new Oracle software can read information from a mainframe, manipulate it on a microcomputer, and store it in the central computer.
A number of Oracle's corporate clients appear excited by the new development. The SNC Group is one of Canada's largest construction consulting firms, with projects around the world. According to Normand Bouffard of SNC, this will allow the company to decentralize control of their far-flung projects completely.
And George Koch of Koch Systems group, which has developed an Oracle-based system for securities trading and accounting, says the micro version will allow Koch to let individual managers ''extract information from their system and fiddle with it,'' something they have been reluctant to allow with other software because of data security problems.