Expert mode query in View objects and appended where clause

Question

My company is Oracle Member Partner and we are developing enterprise web applications using Oracle database and BC4J.
I have the following problem...
When I enable EXPERT MODE option in View Object I have trouble appending to query statement in my client code.
I need expert mode because I must use "SELECT DISTINCT" insted of "SELECT" in my query.
It looks something like this:
viewObject.setWhereClause("CLA_ID = " + claId);
viewObject.executeQuery();
SQL query from View Object becomes sub-query and fails to execute:
select * from (original view object query) where (... appended where clause)
Order by part of the query causes sql errors because original query is now sub-query.
Is there any way around this?

Answer 1

I tried creating an expert mode SQL query:
SELECT DISTINCT EMPNO, ENAME FROM EMP.
Then at runtime I do:
vo.setWhereClause("ENAME LIKE '%'||?||'%');
vo.setWhereClauseParam(0,'A');.
and this works fine. The trick is that since expert-mode view objects get wrapped as inline views (to allow runtime appending of WHERE clause, actually), you need to select any column in the select statement to which you want to later refer in a dynamically-appended where clause.
If you want to prevent the inline-view wrapping, you can write the following code in your view object's ViewObjectImpl subclass to force the VO to NOT be treated as an expert-mode SQL VO.
  // Goes in your view object impl subclass
  public void create() {
     // Force this VO to NOT be treated as an expert-mode SQL, so that
     // its query does not get wrapped as an inline view.
     getViewDef().setFullSql(false);
  }I used this trick above to create an expert mode query like:
SELECT DISTINCT deptno FROM empand then at runtime I add a dynamic where clause that refers to a column
in EMP that is not in the select list like this:
    ViewObject vo = am.findViewObject("View1");
    vo.setWhereClause("ename like '%A%'");
    vo.executeQuery();
    System.out.println(vo.first().getAttribute(0));and this causes the query to come out as:
SELECT DISTINCT deptno FROM emp WHERE ename like '%A%'.
instead of:
SELECT * FROM (SELECT DISTINCT deptno FROM emp) QRSLT WHERE ename like '%A%'which would cause an error due to the fact that ename is not in the select list of the original (wrapped, inline) query.