Consider a "hibernate like" criteria maker:

[gencube]

Hi,

Since there is no plan to turn RxJDBC into a ORM, but perhaps ONLY this portion of the
Library will be useful for the user of your library to avoid the JDBC-(Postgress/MySQL/Oracle/MsSQL...)SQL conversion error.

Consider a hack into this Hibernate Code and how to merge into your library:
How to get SQL from Hibernate Criteria API (not for logging)
http://stackoverflow.com/questions/554481/how-to-get-sql-from-hibernate-criteria-api-not-for-logging

CriteriaImpl criteriaImpl = (CriteriaImpl)criteria;
SessionImplementor session = criteriaImpl.getSession();
SessionFactoryImplementor factory = session.getFactory();
CriteriaQueryTranslator translator=new CriteriaQueryTranslator(factory,criteriaImpl,criteriaImpl.getEntityOrClassName(),CriteriaQueryTranslator.ROOT_SQL_ALIAS);
String[] implementors = factory.getImplementors( criteriaImpl.getEntityOrClassName() );

CriteriaJoinWalker walker = new CriteriaJoinWalker((OuterJoinLoadable)factory.getEntityPersister(implementors[0]), 
                        translator,
                        factory, 
                        criteriaImpl, 
                        criteriaImpl.getEntityOrClassName(), 
                        session.getLoadQueryInfluencers()   );

String sql=walker.getSQLString();

[davidmoten]

yep would be nice, #24 would be a prerequesite.