// effects: Creates a basic cell relation for query
internal BasicCellRelation(CellQuery cellQuery, ViewCellRelation viewCellRelation,
IEnumerable <MemberProjectedSlot> slots)
: base(viewCellRelation.CellNumber)
{
m_cellQuery = cellQuery;
m_slots = new List <MemberProjectedSlot>(slots);
Debug.Assert(m_slots.Count > 0, "Cell relation with not even an exent?");
m_viewCellRelation = viewCellRelation;
}
// effects: Creates a basic cell relation for query
internal BasicCellRelation(CellQuery cellQuery, ViewCellRelation viewCellRelation,
IEnumerable<MemberProjectedSlot> slots)
: base(viewCellRelation.CellNumber)
{
m_cellQuery = cellQuery;
m_slots = new List<MemberProjectedSlot>(slots);
Debug.Assert(m_slots.Count > 0, "Cell relation with not even an exent?");
m_viewCellRelation = viewCellRelation;
}
// effects: Propagates this constraint from the basic cell relation
// to the corresponding view cell relation and returns the new constraint
// If all the key slots are not being projected, returns null
internal ViewKeyConstraint Propagate()
{
ViewCellRelation viewCellRelation = CellRelation.ViewCellRelation;
// If all slots appear in the projection, propagate key constraint
List <ViewCellSlot> viewSlots = new List <ViewCellSlot>();
foreach (MemberProjectedSlot keySlot in KeySlots)
{
ViewCellSlot viewCellSlot = viewCellRelation.LookupViewSlot(keySlot);
if (viewCellSlot == null)
{
// Slot is missing -- no key constraint on the view relation
return(null);
}
viewSlots.Add(viewCellSlot);
}
// Create a key on view relation
ViewKeyConstraint viewKeyConstraint = new ViewKeyConstraint(viewCellRelation, viewSlots);
return(viewKeyConstraint);
}
private void GenerateCellRelations(int cellNumber)
{
// Generate the view cell relation
List<ViewCellSlot> projectedSlots = new List<ViewCellSlot>();
// construct a ViewCellSlot for each slot
Debug.Assert(CQuery.NumProjectedSlots == SQuery.NumProjectedSlots,
"Cell queries in cell have a different number of slots");
for (int i = 0; i < CQuery.NumProjectedSlots; i++)
{
ProjectedSlot cSlot = CQuery.ProjectedSlotAt(i);
ProjectedSlot sSlot = SQuery.ProjectedSlotAt(i);
Debug.Assert(cSlot != null, "Has cell query been normalized?");
Debug.Assert(sSlot != null, "Has cell query been normalized?");
// These slots better be MemberProjectedSlots. We do not have constants etc at this point.
Debug.Assert(cSlot is MemberProjectedSlot, "cSlot is expected to be MemberProjectedSlot");
Debug.Assert(sSlot is MemberProjectedSlot, "sSlot is expected to be MemberProjectedSlot");
MemberProjectedSlot cJoinSlot = (MemberProjectedSlot)cSlot;
MemberProjectedSlot sJoinSlot = (MemberProjectedSlot)sSlot;
ViewCellSlot slot = new ViewCellSlot(i, cJoinSlot, sJoinSlot);
projectedSlots.Add(slot);
}
m_viewCellRelation = new ViewCellRelation(this, projectedSlots, cellNumber);
}
internal void CreateBasicCellRelation(ViewCellRelation viewCellRelation)
{
var slots = GetAllQuerySlots();
// Create a base cell relation that has all the scalar slots of this
m_basicCellRelation = new BasicCellRelation(this, viewCellRelation, slots);
}
