[xwiki-devs] [proposal] Move away from XWQL, it is invalid JPQL (JPA) thus it is it's own (undefined) standard.

After searching through documentation on JPQL (JPA's query language) I was unable to find any example of the "doc.object(XWiki.XWikiUsers)" construct. This means XWQL is it's own standard and there is no authoritative reference on it. What makes an implementation compliant? I have found that most HQL queries can be executed as XWQL queries with little or no modification so if compliance is defined as being "just like the reference implementation" then nearly all HQL must be implemented in order to be compliant. Looking at the specifications I have rewritten the example query in compliant JPQL and JDOQL. I wrote these so that they would work if all objects were custom mapped which is similar to the appearance XWQL gives. XWQL: (SELECT doc.fullName FROM XWikiDocument as doc) where doc.author = 'XWiki.LudovicDubost' and doc.object(XWiki.XWikiUsers).email like '%xwiki.com' JPQL: SELECT doc.fullName FROM XWikiDocument as doc, IN(doc.xObjects) obj WHERE obj.className = 'XWiki.XWikiUsers' and obj.email LIKE '%xwiki.com' JDOQL: SELECT this.fullName FROM XWikiDocument WHERE this.xObjects.containsValue(obj) && obj.className == "XWiki.XWikiUsers" && obj.email.startsWith("xwiki.com") I understood that XWQL was simply a translation scheme which made it appear that we were using JPQL with the schema we wanted when really we were using HQL with the schema we had. Given that it is not compliant JPQL that is not the case. I think when we update the schema, we should cut our losses with this thing and move to something which has a reference document and is more widely used. WDYT? Caleb The JPQL specification (originally called EJBQL): ejb-3_0-fr-spec-ejbcore.pdf chapter 9. http://jcp.org/aboutJava/communityprocess/final/jsr220/ The JDOQL specification: jdo-3_0-mrel3-spec.pdf chapter 26. http://db.apache.org/jdo/specifications.html Easy to read, example rich descriptions: http://www.datanucleus.org/products/accessplatform_3_0/jpa/jpql.html http://www.datanucleus.org/products/accessplatform_3_0/jdo/jdoql.html