[SPARK-21848] Create trait to identify user-defined functions

• Type: Task
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.2.0
• Fix Version/s: 2.3.0
• Component/s: SQL
• Assignee: Gengliang Wang
• Reporter: Gengliang Wang
• Created: 28/Aug/17 04:53
• Updated: 29/Aug/17 16:09
• Resolved: 29/Aug/17 16:09

Description

Create a trait to make it easier for identifying what expressions are user-defined functions

Issue Links

• links to: [Github] Pull Request #19064 (gengliangwang)