[IMPALA-6398] Can we add comment in select list

• Type: New Feature
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Component/s: Frontend
• Epic Color: ghx-label-1
• Assignee: Unassigned
• Reporter: Jiecheng Zhao
• Created: 16/Jan/18 01:27
• Updated: 26/Feb/18 08:37

Description

When we working, we always write code like
'''
CREATE TABLE xxxx AS
SELECT
  exp_of_a item_a – comment for a 
, exp_of_b item_b – comment for b
, exp_of_c item_c – comment for c
FROM ...
'''. 
Can we capture the comments of the item or design some syntax at these places and add these info into table column comment naturally? (instead of adding comment separately in current syntax) 

I have looked at the source code and found we should have nothing like this now.
https://github.com/cloudera/Impala/blob/114ac271fa4ac991d7c3392128354c0d056cb975/fe/src/main/cup/sql-parser.cup#L2301