[IMPALA-3602] Implement percentile and percentile_approx statistical functions

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: Impala 2.6.0
• Component/s: Backend
• Labels: built-in-function ramp-up
• Target Version: Product Backlog
• Assignee: Unassigned
• Reporter: Lars Volker
• Created: 24/May/16 09:51
• Updated: 14/Mar/18 04:29

Description

We should implement those statistical functions. Hive supports them: https://cwiki.apache.org/confluence/display/Hive/LanguageManual+UDF

• percentile
• percentile_approx

Issue Links

• duplicates: IMPALA-4025 add functions PERCENTILE_DISC(), PERCENTILE_CONT(), and MEDIAN()