public Criteria(Criteria toCopy)
{
ignoreCase = toCopy.ignoreCase;
singleRecord = toCopy.singleRecord;
selectModifiers = new UniqueList<String>(toCopy.selectModifiers);
selectColumns = new UniqueColumnList(toCopy.selectColumns);
orderByColumns = new UniqueList<OrderBy>(toCopy.orderByColumns);
groupByColumns = new UniqueColumnList(toCopy.groupByColumns);
fromElements = new UniqueList<FromElement>(toCopy.fromElements);
if (toCopy.having != null)
{
having = new Criterion(toCopy.having);
}