[IMPALA-3210] last_value()/first_value() support for IGNORE NULLS

• Type: New Feature
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Impala 2.0
• Fix Version/s: Impala 2.7.0
• Component/s: Backend
• Labels: compatibility ramp-up
• Target Version: Product Backlog
• Assignee: Thomas Tauber-Marshall
• Reporter: Matthew Jacobs
• Created: 18/Mar/16 16:48
• Updated: 18/Jul/16 17:00
• Resolved: 18/Jul/16 17:00

Description

Add support for the first_value() and last_value() analytic functions to ignore nulls, e.g. returning the first/last non-null value in the window.

For example,

LAST_VALUE ( expression [ IGNORE NULLS ] ) OVER ( ... )