db-jdo-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Andy Jefferson <a...@datanucleus.org>
Subject Re: Minutes: JDO TCK Conference Call Friday, Aug 22, 9 am PDT
Date Fri, 22 Aug 2008 17:39:41 GMT
> 2. There is one issue that is a bug in the reference implementation
> https://issues.apache.org/jira/browse/JDO-573 Is this going to be fixed any
> time soon?

The short answer is no.

The long answer is as follows. The JDOQL process used by the DataNucleus RDBMS 
plugin uses the mechanism that TJDO wrote (pretty much the only part of TJDO 
that remains in the codebase). This mechanism doesn't have a full expression 
tree, and consequently is not a simple process to convert into SQL, nor to 
extend. This results in it being difficult to fix very complex queries such 
as the one in that test without breaking something else. The strategic 
solution is to replace the mechanism by a more generic process that does 
create an expression tree, which can then be converted into SQL. The generic 
compilation is largely written (and used by all other supported datastores), 
but the process of conversion from the expression tree into SQL is not 
written. I have the writing of this expression tree to SQL converter down for 
DataNucleus AccessPlatform 1.1. Obviously if people offered their time to 
work on these things then they'd get done much sooner.

I'd *suggest* that JDO-573 be deferred to a later Apache JDO release.


-- 
Andy  (DataNucleus - http://www.datanucleus.org)

Mime
View raw message