[hibernate-issues] [Hibernate-JIRA] Commented: (HHH-465) order by nulls first / last

[Steve Ebersole (JIRA)]

    [ http://opensource.atlassian.com/projects/hibernate/browse/HHH-465?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=33012#action_33012 ] 

Steve Ebersole commented on HHH-465:
------------------------------------

In the interest of completeness, it is actually the SQL-2003 spec which introduces NULLS FIRST | NULLS LAST.

Also, it does not define the "sort key" as simply as [COLUMN NAME].  In SQL-92 it was the case that a sort-key could only be (a) column name or (b) integer literal (indicating the select-clause position).  For SQL-2003 (and SQL-99), the full definition of sort key is:
<sort key>    ::=   <value expression>
essentially anything that resolves to a value (see http://savage.net.au/SQL/sql-2003-2.bnf.html#sort%20key for details)

The difficulty here is if we are going to support SQL-2003 then we need to support its full breadth.  Which implies an audit to see what databases fully comply with the various SQL-2003 defined compatibility levels.

> order by nulls first / last
> ---------------------------
>
>                 Key: HHH-465
>                 URL: http://opensource.atlassian.com/projects/hibernate/browse/HHH-465
>             Project: Hibernate Core
>          Issue Type: Improvement
>          Components: core
>    Affects Versions: 3.0.3
>            Reporter: Anthony Patricio
>            Priority: Minor
>         Attachments: CustomNullsFirstInterceptor.java
>
>
> support of nulls first / last in order clause
> "NULLS LAST" is part of the SQL 99 standard. 
> The syntax is as follows: 
> ORDER BY [COLUMN NAME] [ASC | DESC] [NULLS FIRST | NULLS LAST] 
> In different DBs, the sorting of nulls relative to other values is handled differently. 
> PostgreSQL - Nulls are considered HIGHER than non-nulls. 
> DB2 - Higher 
> MSSQL - Lower 
> MySQL - Lower 
> Oracle - Higher 
> The following DBs have supported this functionality: 
> DB2 V7 
> Oracle 9i 
> PostgreSQL, MySQL, SQLServer do not appear to support this from what I can gather.
> see http://forum.hibernate.org/viewtopic.php?t=942176&start=0&postdays=0&postorder=asc&highlight=

-- 
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators: http://opensource.atlassian.com/projects/hibernate/secure/Administrators.jspa
-
For more information on JIRA, see: http://www.atlassian.com/software/jira