{{Short description|Computer produced by Teradata Corporation}} The '''DBC/1012''' Data Base Computer was a database machine introduced by Teradata Corporation in 1984, as a back-end data base management system for mainframe computers.<ref>{{Cite news |title= Will Teradata revive a market? |author= Paul Gillin |pages= 43, 48 |work= Computer World |date= February 20, 1984 |url= https://books.google.com/books?id=5pw6ePUC8YYC&pg=PA48 |access-date= March 13, 2017 }}</ref> The DBC/1012 harnessed multiple Intel microprocessors, each with its own dedicated disk drive, by interconnecting them with the Ynet switching network in a massively parallel processing system.<ref>{{Cite journal |title= The benefits of database computers |date= April 15, 1991 |journal= Second International Specialist Seminar on the Design and Application of Parallel Digital Processors |author= J. Page |pages= 112–117 |isbn= 0-85296-519-2 }}</ref><ref>{{Cite book |date= January 7, 1992 |author= R. D. Sloan |title= Proceedings of the Twenty-Fifth Hawaii International Conference on System Sciences |chapter= A practical implementation of the data base machine-Teradata DBC/1012 |pages= 320-327 vol.1 |doi= 10.1109/HICSS.1992.183180 |isbn= 0-8186-2420-5 |s2cid= 62020363 }}</ref> The DBC/1012 was designed to manage databases up to one terabyte (1,000,000,000,000 characters) in size; "1012" in the name refers to "10 to the power of 12".<ref>{{Cite book |title= Past, Present, Parallel: A Survey of Available Parallel Computer Systems |pages= 226–231 |editor= Arthur Trew |editor2=Greg Wilson |date= December 6, 2012 |publisher=Springer Science & Business Media |isbn= 9781447118428 |url= https://books.google.com/books?id=HZzeBwAAQBAJ&pg=PA226 |access-date= March 13, 2017 }}</ref>
thumb|right|Image of Teradata DBC/1012 from its 1987 brochure
Major components included:
* Mainframe-resident software to manage users and transfer data * Interface processor (IFP) - the hardware connection between the mainframe and the DBC/1012 * Ynet - a custom-built system interconnect that supported broadcast and sorting * Access module processor (AMP) - the unit of parallelism: includes microprocessor, disk drive, file system, and database software * System console and printer * TEQUEL (TEradata QUEry Language) - an extension of SQL
The DBC/1012 was designed to scale up to 1024 Ynet interconnected processor-disk units. Rows of a relation (table) were distributed by hashing on the primary database index.
The DBC/1012 used a 474 megabyte Winchester disk drive with an average seek time of 18 milliseconds. The disk drive was capable of transferring data at 1.9 MB/s although in practice the sustainable data rate was lower because the IO pattern tended towards random access and transfer lengths of 8 to 12 kilobytes.
The processor cabinet was 60 inches high and 27 inches wide, weighed 450 pounds, and held up to 8 microprocessor units. The storage cabinet was 60 inches high and 27 inches wide, weighed 625 pounds, and held up to 4 disk storage units.
The DBC/1012 preceded the advent of redundant array of independent disks (RAID) technology, so data protection was provided by the "fallback" feature, which kept a logical copy of rows of a relation on different AMPs. The collection of AMPs that provided this protection for each other was called a cluster. A cluster could have from 2 to 16 AMPs.
The product could be integrated with optical disc drives.<ref>{{Cite book |date= May 7, 1990 |publisher= IEEE |author= N.C. Ramsay |title= [1990] Digest of papers. Tenth IEEE Symposium on Mass Storage Systems@m_Crisis in Mass Storage |chapter= Integration of the optical storage processor and the DBC/1012 database computer |pages= 94–97 |doi= 10.1109/MASS.1990.113576 |isbn= 0-8186-2034-X |s2cid= 33985588 }}</ref> There were at least four models, marketed through about 1993.<ref>{{Cite web |title= AT&T / NCR Products 1992 & 1993 Catalogue: DBC/1012 Model 4 |work= Website of the UK Retirement Fellowship |url= http://www.ncr.org.uk/page468.html |access-date= March 13, 2017 |archive-url= https://web.archive.org/web/20170314153348/http://www.ncr.org.uk/page468.html |archive-date= March 14, 2017 |url-status= dead }}</ref><ref>{{Cite web |title= Colior image of TeradataDBC/1012 Data Base Computer with front covers removed |work= Artifact detail |publisher= Computer History Museum |url= http://www.computerhistory.org/collections/catalog/102713122 |access-date= March 13, 2017 }}</ref>
==References== {{Reflist}}
{{DEFAULTSORT:Dbc 1012}} Category:Mainframe computers Category:Teradata