I read somewhere that v2.2 will include an interface to the HQL parser. I am interested in whether this will allow me to use db specific functions by customising the dialects. Functions like isnull, dateadd etc from SQLServer.

For example dateadd().

In SQLServer:

dateadd( getdate(), dd, 5 ) // add 5 days

Oracle

sysdate + interval '5' day

MySQL

now() + interval 5 day

So would it be possible to define my own pseudo function ( say dateadd() )like SQLServer and write a plugin that will convert dateadd( x, y, z ) to the relevant syntax depending on the dialect, or alternatively write a new dialect for each db to do this?

Is this what the parser will be able to do or is there some other way of achieving the above, either now or in 2.2 with the new parser?

Any information or suggestions would be appreciated as would a rough guess as to when 2.2 might be available.

I have looked at the JDBC functions ( TIMESTAMPADD ) but no Oracle JDBC driver seems to support it.

Cheers.

Hibernate 3.0 will have a new parser for HQL which will make extending current DB function support feature set and adding arithmetic operations much easier. How much is completed above current support and when cannot currently be discussed since its not in stone as yet. The final is some time off but beta will start soon(ish).