Inverse Distribution Functions

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(Created page with "=== Inverse Distribution Functions === Defined in the SQL standard in Section 10.9 <aggregate function>, inverse distribution functions open whole new vistas both of reporting a…")
 
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=== Inverse Distribution Functions ===
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= Inverse Distribution Functions =
  
 
Defined in the SQL standard in Section 10.9 <aggregate function>,
 
Defined in the SQL standard in Section 10.9 <aggregate function>,
 
inverse distribution functions open whole new vistas both of
 
inverse distribution functions open whole new vistas both of
 
reporting and of implementation challenges.
 
reporting and of implementation challenges.
 +
 +
= Vistas of Reporting =
 +
 +
* MEDIAN! YAY!
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* N-tiles (continuous and discrete)
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* Many others.
 +
 +
= Implementation Challenges =
 +
 +
* Parser
 +
** Mostly done.  Thanks, Atri Sharma!
 +
** WITHIN GROUP clause
 +
 +
* Planner/Optimizer
 +
** In progress
 +
** Really applies atop FILTER, not yet in master.
 +
** New element in ProcedureCreate
 +
* Executor
 +
** New way to do aggregates: transition function now optional.

Revision as of 02:53, 3 June 2013

Inverse Distribution Functions

Defined in the SQL standard in Section 10.9 <aggregate function>, inverse distribution functions open whole new vistas both of reporting and of implementation challenges.

Vistas of Reporting

  • MEDIAN! YAY!
  • N-tiles (continuous and discrete)
  • Many others.

Implementation Challenges

  • Parser
    • Mostly done. Thanks, Atri Sharma!
    • WITHIN GROUP clause
  • Planner/Optimizer
    • In progress
    • Really applies atop FILTER, not yet in master.
    • New element in ProcedureCreate
  • Executor
    • New way to do aggregates: transition function now optional.
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