Bug 164764 Joint data set does not work properly using attached flatfile
The data set preview keep empty in joint data set. Step to reproduce: 1.Create two data sets based on attached flat file 2.Make an inner join using joint data set with key "A". 3.Preview data set in data set editor. Expect result: The data set preview correctly Actual result: The data set preview is empty.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/script/ScriptEvalUtil.java
result = resultObject == null;
				break;
			case IConditionalExpression.OP_NOT_NULL :
				result = resultObject != null;
				break;
			case IConditionalExpression.OP_TRUE :
				result = isTrueOrFalse( resultObject, Boolean.TRUE );
				break;
			case IConditionalExpression.OP_FALSE :
				result = isTrueOrFalse( resultObject, Boolean.FALSE );
				break;
			case IConditionalExpression.OP_LIKE :
				result = like( resultObject, resultOp1 );
				break;
			case IConditionalExpression.OP_NOT_LIKE :
				result = !like( resultObject, resultOp1 );
				break;
				
			case IConditionalExpression.OP_TOP_N :
			case IConditionalExpression.OP_BOTTOM_N :
			case IConditionalExpression.OP_TOP_PERCENT :
			case IConditionalExpression.OP_BOTTOM_PERCENT :
				
				throw new DataException(
						ResourceConstants.UNSUPPORTTED_COND_OPERATOR, "Top/Bottom(N) outside of row filters" );
				
		/*	case IConditionalExpression.OP_ANY :
				throw new DataException(
						ResourceConstants.UNSUPPORTTED_COND_OPERATOR, "ANY" );*/
			case IConditionalExpression.OP_MATCH :