[
https://issues.apache.org/jira/browse/DERBY-5893?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13428636#comment-13428636
]
Bryan Pendleton commented on DERBY-5893:
----------------------------------------
Does IS DISTINCT FROM mean something different than != ?
What does it look like in sample queries?
> Add support for the SQL:2008 standard IS [ NOT ] DISTINCT FROM predicate
> ------------------------------------------------------------------------
>
> Key: DERBY-5893
> URL: https://issues.apache.org/jira/browse/DERBY-5893
> Project: Derby
> Issue Type: Improvement
> Components: SQL
> Affects Versions: 10.9.1.0
> Reporter: Lukas Eder
> Priority: Minor
> Labels: features
>
> The SQL:1999 standard specifies the IS [ NOT ] DISTINCT FROM predicate in
> chapter 8.15 <distinct predicate>:
> <distinct predicate> ::=
> <row value predicand 3> <distinct predicate part 2>
> <distinct predicate part 2> ::=
> IS [ NOT ] DISTINCT FROM <row value predicand 4>
> <row value predicand 3> ::=
> <row value predicand>
> <row value predicand 4> ::=
> <row value predicand>
> This predicate is supported by at least these databases:
> - http://www.postgresql.org/docs/9.1/static/functions-comparison.html
> - http://www.h2database.com/html/grammar.html#condition_right_hand_side
> - http://hsqldb.org/doc/guide/ch05.html#N11BB0
> -
> http://dev.mysql.com/doc/refman/5.6/en/comparison-operators.html#operator_equal-to
> (with a different syntax)
> -
> http://dcx.sybase.com/1200/en/dbreference/is-distinct-from-search-condition.html
> It would probably make sense for the Derby database to implement it as well.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators:
https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira
