DDC 775

[FabioBatSilva]

Hello

http://www.doctrine-project.org/jira/browse/DDC-775

This patch adds support for arithmetic expression, case expression and functions on DQL ORDER BY clause.

Please let me know if can I make something better :)

Thanks

[stof]

Functions in the ORDER BY clause are not cross-platform. This has already been rejected for this reason.

As of 2.2, you can achieve the result using the HIDDEN keyword in the SELECT clause to exclude it from the result set:

SELECT u, HIDDEN IDENTITY(u.email) as email FROM Doctrine\Tests\Models\CMS\CmsUser u ORDER BY email

[beberlei]

Any way to automatically move expression in OrderBy into the select clause and use the alias in Order By?

[stof]

@beberlei we discussed it with @guilhermeblanco a while ago on IRC and we both agreed that this would make the code more complex and that it can already be achieved using HIDDEN in 2.2. Our conclusion was that the best solution would be to improve the doc to explain how to achieve it with the current code (but I'm not sure if he worked on the doc after that)

[FabioBatSilva]

Sorry,

I did not attend the previous discussion, how many databases do not support this ?
On Hibernate SQL functions are allowed if they are supported by the underlying database.

I suggest documenting this behavior in databases that do not support functions, instead of limit this feature in all databases.
maybe a flag in DBAL to tell us whether this is supported, otherwise throws an exception.

[guilhermeblanco]

@FabioBatSilva Are you sure? JPA v2 points at page 106 this:

orderby_clause ::= ORDER BY orderby_item {, orderby_item}* 
orderby_item ::= state_field_path_expression [ASC | DESC]

If Hibernate supports it, it's not documented I think. Official docs doesn't point anything either.

[guilhermeblanco]

@FabioBatSilva @beberlei @stof @asm89 Ok, here is the deal.
I took some deeper look at the patch, and we may support some of the features you are proposing.

Here is your original proposal:

OrderByItem ::= (
     SimpleArithmeticExpression | SingleValuedPathExpression | CaseExpression |
     ScalarExpression | AggregateExpression | FunctionDeclaration | ResultVariable
) ["ASC" | "DESC"]

Here is my suggestion:

OrderByItem ::= (
     SimpleArithmeticExpression | SingleValuedPathExpression | ScalarExpression | ResultVariable
) ["ASC" | "DESC"]

[FabioBatSilva]

hello @guilhermeblanco,

i'm fine with your suggestion :)

But Hibernate and NHibernate allow functions and aggregate functions in the user documentation.
In both cases there are specifications for the support of the database.
if I remember right EJB does not support this feature.

NHibernate : http://nhforge.org/doc/nh/en/index.html#queryhql-ordering
Hibernate : http://docs.jboss.org/hibernate/orm/3.5/reference/en/html/queryhql.html#queryhql-ordering

Hibernate Docs : SQL functions and aggregate functions are allowed in the having and order by clauses if they are supported by the underlying database (i.e., not in MySQL).

[FabioBatSilva]

Hi guys.
I change the patch to use the proposal from @guilhermeblanco.

Please take a look

[stof]

changing the indentation is wrong here

[FabioBatSilva]

done !!