Teradata interview questions FAQs

How teradata makes sure that there are no duplicate rows being inserted when its a SET table?
Teradata redirects the new inserted row as per its Primary Index to the target AMP (Access Module Processor) on the basis of its row hash value, and if it find same row hash value in that AMP then it start comparing the whole row, and find out if duplicate.
When the target table has UPI(Unique Primary Index) then the duplicate row is rejected with an error.
In case of a NUPI(Non-Unique Primary Index) then it is rejected without throwing any error

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BYNET

DEFINITION BYNET, acronym for "BanYan NETwork," is a folded banyan switching network built upon the capacity of the YNET. It acts as a distributed multi-fabric inter-connect to link PEs, AMPs and nodes on a Massively Parallel Processing (MPP) system. OVERVIEW Interconnect technology is important for parallel computing. The BYNET is Teradata's "system interconnect for high-speed, fault tolerant warehouse-optimized messaging between nodes." [11] As an indispensable part of the Teradata MPP system, it can be understood better with its predecessor "YNET" in the background. In 1982, the YNET interconnecting technology used on the DBC 1012 was patented for the parallelism. As a broadcast-based hardware solution, it linked all the IFPs, COPs, and AMPs together with circuit boards and cables in a dual bus architecture. Two costom-built busses operated concurrently within the interconnect framework: YNET A to connect the IFPs and COPs on one side, and YNET

SET VS MULTISET

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