60     m_field.reset(rhs.
m_field.get() ? m_field->clone() : 0);
 
GroupByItem & operator=(const GroupByItem &rhs)
 
A class that can be used in a GROUP BY clause. 
 
A class that models the name of any property of an object. 
 
A class that models the name of any property of an object. 
 
Expression * getExpression() const 
It returns the exprsssion to be used to sort the result of a query. 
 
This is an abstract class that models a query expression. 
 
~GroupByItem()
Destructor. 
 
GroupByItem(const Expression &e)
Constructor. 
 
This is an abstract class that models a query expression. 
 
A class that can be used in a GROUP BY clause. 
 
std::auto_ptr< Expression > m_field
A valid expression. 
 
void setExpression(Expression *e)
It sets the expression to sort the result of a query.