want ofbiz support complex sql

[和风赛跑]

Hello friends,
 ofbiz encapsulates operations between entities and entity fields,but if I have 
a very complex sql,it is difficult for ofbiz.
 I want I have a function like iBatis support the dynamic query in ofbiz.Is it 
difficult?
 By the way ,if I want to write the basic jdbc sql to invoke,and pass the sql 
to ofbiz,how should I do?
  
 I donot like the ofbiz encapsulates operations between entities and entity 
fields,because its process is complex and difficult to  get the actually sql at 
runtime.