Bug 131011 Support running query based on report document data
Data Engine should support running a query based on data set and expression data stored in a report document. This bugzilla entry serves as a repository for design docs and notes related to this feature.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/api/querydefn/BaseTransform.java
* @return the sort criteria
	 */
	
	public List getSorts( )
	{
		return sorts;
	}
	
	/**
	 * Appends one sort definition to the list of sort criteria
	 */
	public void addSort( SortDefinition sort) 
	{
		sorts.add(sort);
	}
	/**
	 * Add one Javascript expression to the list of expressions that needs evaluation as part 
	 * of this transform. 
	 * expressionTiming can be <br>
	 * <code>BEFORE_FIRST_ROW</code>: expression is evaluated at the start of the iteration over the row set for this gorup/list <br>
	 * <code>AFTER_LAST_ROW</code>: expression is evaluated at the end of the iteration<br>
	 * <code>ON_EACH_ROW</code>: expression is evaluated with each detail row within the group/list <br>  
	 * @deprecated use addResultSetExpression( ) instead
	 */
	public void addExpression(IBaseExpression expression, int expressionTiming ) 
	{
	    if ( expressionTiming == BEFORE_FIRST_ROW )
	    {
	        beforeExpressions.add( expression );
	    }