Hash Maps in TeraData

Hash Maps

DSW (Distribution Selection Word)

Inclined to build a profession as Teradata Developer? Then here is the blog post on, explore Teradata Training

Hash Map provides a relationship between row hash value[DSW] and Amp address Primary index Physical Mechanism [Storage & retrieval Party id mechanism]     

The  dates distribution in the Amp’s and amp contains the data in rowed logical Sequence  

Inside the Amp

Sel * From party where Pid=2

Teradata Interview Questions

Hash synonym(or) Hash collisions

• Getting the same row hash values for the same (or) to PI value is called hash synonym(or) Hash collision.
• In this situation to identify every row system takes a concept called rowed.
• It is useful to identify every record unique in the amp.
• It is taken by the amp only.
• It contains 64 bits first 32 bits are row hash value, next 32 bits are u values.