[CALCITE-2476] SqlAdvisor: lack of hints when sub-query has STAR (simplifySql produces 0 AS "*")

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.17.0
• Fix Version/s: 1.18.0
• Component/s: core
• Assignee: Julian Hyde
• Reporter: Vladimir Sitnikov
• Created: 19/Aug/18 15:12
• Updated: 23/Dec/18 00:12
• Resolved: 05/Sep/18 13:54

Description

SimpleSqlParser.purgeSelectExprsKeepAliases tries to replace expressions in select clause with aliases, and it often produces invalid SQL:

select * from dummy is replaced with select 0 AS "*" from dummy which is invalid
select a.x+ b.y from dummy is replaced with select 0 AS "b.y" from dummy and so on.

Testcase:

select ax^ from (select * from dummy a)

Actual output:

SELECT ax _suggest_ FROM ( SELECT 0 AS * FROM dummy a )

I'm inclined to comment purgeSelectExprsKeepAliases out for now.

Issue Links

• links to: PR 773