Forbid NEXT VALUE FOR clause in certain contexts
------------------------------------------------
Key: DERBY-4513
URL: https://issues.apache.org/jira/browse/DERBY-4513
Project: Derby
Issue Type: Bug
Components: SQL
Affects Versions: 10.6.0.0
Reporter: Rick Hillegas
This is part of the work needed to implement ANSI/ISO sequences. The functional
spec attached to DERBY-712 lists various situations in which the NEXT VALUE FOR
clause is illegal. These include:
* CASE expression
* WHERE clause
* ORDER BY clause
* AGGREGATE expression
* WINDOW function
* DISTINCT select list
In addition, I propose that we make it illegal for a statement to have more
than one NEXT VALUE FOR clause on the same sequence generator. This is a
tighter restriction than the ANSI/ISO standard calls for. The standard requires
that if two columns in a row are populated by NEXT VALUE FOR clauses on the
same sequence, then the values should be the same. I don't feel confident that
I could track down all of the cases which could give rise to this situation--so
I propose to limit the number of NEXT VALUE FOR clauses on a given sequence
generator to just 1.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
