[DRILL-4270] Create a separate WindowFramer that supports the FRAME clause

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.5.0
• Fix Version/s: Future
• Component/s: Execution - Relational Operators
• Assignee: Abdel Hakim Deneche
• Reporter: Abdel Hakim Deneche
• Created: 13/Jan/16 18:52
• Updated: 21/Jan/16 20:39
• Resolved: 21/Jan/16 20:39

Description

Currently most the window functions logic is handled by DefaultFrameTemplate. Create a separate CustomFrameTemplate that handles the FRAME clause, this should make the code in both classes more focused and will make it easier for us to add support for the FRAME clause.

Aggregations, FIRST_VALUE and LAST_VALUE will be handled by CustomFrameTemplate, and all remaining window functions (Ranking, ROW_NUMBER, LEAD and LAG) will be handled by DefaultFrameTemplate.