Bug #74539 view creation with named columns, over union, is rejected

• Submitted: 24 Oct 2014 8:40
• Modified: 23 Jul 2015 18:27
• Reporter: Guilhem Bichot
• Status: Closed
• Category: MySQL Server: DDL
• Severity: S3 (Non-critical)
• Version: 5.6.20
• OS: Any
• CPU Architecture: Any

[24 Oct 2014 8:40] Guilhem Bichot

Description:
When working on http://bugs.mysql.com/bug.php?id=74496
noticed this:

create view v (vv,ww) as SELECT 1 AS a, 2 AS b UNION ALL  SELECT 1 AS a, 1 AS a;
ERROR 1060 (42S21): Duplicate column name 'a'

this should be accepted.

How to repeat:
create view v (vv,ww) as SELECT 1 AS a, 2 AS b UNION ALL  SELECT 1 AS a, 1 AS a;

[23 Jul 2015 18:27] Paul DuBois

Noted in 5.5.46, 5.6.27, 5.7.9, 5.8.0 changelogs.

View creation from a UNION failed with a duplicate-column error if
multiple SELECT statements in the UNION used the same column name.

[24 Jul 2015 12:57] Paul DuBois

Revised changelog entry:

View creation from a UNION failed with a duplicate-column error if a
SELECT statement in the UNION other than the first used the same
column name multiple times.