[DRILL-1248] Add support for using aliases in group by

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.15.0
• Component/s: SQL Parser
• Labels: doc-complete ready-to-commit
• Assignee: Arina Ielchiieva
• Reporter: Jim Scott
• Reviewer: Vova Vysotskyi
• Created: 02/Aug/14 03:49
• Updated: 08/Jul/19 17:02
• Resolved: 14/Sep/18 22:52

Description

when I select using a function and alias the resultant function value it won't parse properly saying the alias is ambiguous. I know that this is a debatable / questionable topic, but with this engine being so flexible it seems that in order to support all of the formatting, casting, etc.. that will likely occur having the group by support an alias would be a big deal. This in my opinion is nothing like an ordinal group by.

This works:
select extract(year from to_date(crimes.datetime, 'MM/DD/YYYY hh:mm:ss a')) from BLAH group by extract(year from to_date(crimes.datetime, 'MM/DD/YYYY hh:mm:ss a'));

This doesn't:
select extract(year from to_date(crimes.datetime, 'MM/DD/YYYY hh:mm:ss a')) as mygroup from BLAH group by mygroup

For documentation
Positional / named alias are allowed in group by / order by / having clauses:

select length(n_name), n_regionkey from cp.`tpch/nation.parquet` group by 1, 2;
select length(n_name) as len, n_regionkey as key from cp.`tpch/nation.parquet` group by len, key;
select length(n_name) as len, count(*) as cnt from cp.`tpch/nation.parquet` group by length(n_name) having cnt > 1;
select n_regionkey, n_name from cp.`tpch/nation.parquet` order by 1, 2;
select n_regionkey as r, n_name as n from cp.`tpch/nation.parquet` order by r, n;

Issue Links

• relates to: DRILL-4912 Ability to use alias in join conditions
• links to: GitHub Pull Request #1461