public Query clone()
{
Query q = new Query();
q.setMaxRows(_maxRows);
q.setFirstRow(_firstRow);
q.getSelectClause().setDistinct(_selectClause.isDistinct());
foreach (FromItem item in _fromClause.getItems())
{
q.from(item.clone());
}
foreach (SelectItem item in _selectClause.getItems())
{
q.select(item.clone(q));
}
foreach (FilterItem item in _whereClause.getItems())
{
q.where (item.clone());
}
foreach (GroupByItem item in _groupByClause.getItems())
{
q.groupBy(item.clone());
}
foreach (FilterItem item in _havingClause.getItems())
{
q.having(item.clone());
}
foreach (OrderByItem item in _orderByClause.getItems())
{
q.orderBy(item.clone());
}
return(q);
} // clone()
} // executeQuery()
/**
* Determines if all the select items are 'simple' meaning that they just
* represent scans of values in columns.
*
* @param clause
* @return
*/
private bool isSimpleSelect(SelectClause clause)
{
if (clause.isDistinct())
{
return(false);
}
foreach (SelectItem item in clause.getItems())
{
if (item.getAggregateFunction() != null || item.getExpression() != null)
{
return(false);
}
}
return(true);
} // isSimpleSelect()