[ https://issues.apache.org/jira/browse/PIG-2167?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Daniel Dai updated PIG-2167: ---------------------------- Description: Computing aggregates over a cube of several dimensions is a common operation in data warehousing. The standard SQL syntax is "GROUP relation BY dim1, dim2, dim3 WITH CUBE" -- which in addition to all dim1-2-3, produces aggregations for just dim1, just dim1 and dim2, etc. NULL is generally used to represent "all". A presentation by Arnab Nandi describes how one might implement efficient cubing in Map-Reduce here: http://pdf.cx/44wrk We can start with the naive solution which only works for algebraic measures, and work up from there. This is a candidate project for Google summer of code 2012. More information about the program can be found at https://cwiki.apache.org/confluence/display/PIG/GSoc2012 was: Computing aggregates over a cube of several dimensions is a common operation in data warehousing. The standard SQL syntax is "GROUP relation BY dim1, dim2, dim3 WITH CUBE" -- which in addition to all dim1-2-3, produces aggregations for just dim1, just dim1 and dim2, etc. NULL is generally used to represent "all". A presentation by Arnab Nandi describes how one might implement efficient cubing in Map-Reduce here: http://pdf.cx/44wrk We can start with the naive solution which only works for algebraic measures, and work up from there. > CUBE operation in Pig > --------------------- > > Key: PIG-2167 > URL: https://issues.apache.org/jira/browse/PIG-2167 > Project: Pig > Issue Type: New Feature > Reporter: Dmitriy V. Ryaboy > Labels: gsoc2012 > > Computing aggregates over a cube of several dimensions is a common operation > in data warehousing. > The standard SQL syntax is "GROUP relation BY dim1, dim2, dim3 WITH CUBE" -- > which in addition to all dim1-2-3, produces aggregations for just dim1, just > dim1 and dim2, etc. NULL is generally used to represent "all". > A presentation by Arnab Nandi describes how one might implement efficient > cubing in Map-Reduce here: http://pdf.cx/44wrk > We can start with the naive solution which only works for algebraic measures, > and work up from there. > This is a candidate project for Google summer of code 2012. More information > about the program can be found at > https://cwiki.apache.org/confluence/display/PIG/GSoc2012 -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira