7.00.02 - SQL-MapReduce Call - Aster Analytics

Teradata Aster® Analytics Foundation User GuideUpdate 2

Product
Aster Analytics
Release Number
7.00.02
Published
September 2017
Content Type
Programming Reference
User Guide
Publication ID
B700-1022-700K
Language
English (United States)
Last Update
2018-04-17
SELECT *
  FROM minhash(
  ON (SELECT 1)
  PARTITION BY 1
  InputTable ('salesdata')
  OutputTable ('minhashoutput')
  IDColumn ('userid')
  ItemsColumn ('itemid')
  HashNum ('1002')
  KeyGroups ('3')
  InputType ('integer')
  MinClusterSize ('3')
  MaxClusterSize ('5')
);

The number of hash functions must be an integer multiple of number of keygroups, while each clusterid is generated by concatenating KeyGroups’ hashcodes together. The larger the amount of keygroups, fewer clusters are obtained.