// requires: caseForOuterJoins corresponds the slot "slotNum"
// effects: Adds a WhenThen corresponding to child to caseForOuterJoins.
private void AddCaseForOuterJoins(CaseStatement caseForOuterJoins, CqlBlock child, int slotNum, CqlIdentifiers identifiers)
{
// Determine the cells that the slot comes from
// and make an OR expression, e.g., WHEN _from0 or _from2 or ... THEN child[slotNum]
ProjectedSlot childSlot = child.SlotValue(slotNum);
ConstantProjectedSlot constantSlot = childSlot as ConstantProjectedSlot;
if (constantSlot != null && constantSlot.CellConstant.IsNull())
{
// NULL being generated by a child - don't need to project
return;
}
BoolExpression originBool = BoolExpression.False;
for (int i = 0; i < NumBoolSlots; i++)
{
int boolSlotNum = BoolIndexToSlot(i);
if (child.IsProjected(boolSlotNum))
{
// OR it to the expression
QualifiedCellIdBoolean boolExpr = new QualifiedCellIdBoolean(child, identifiers, i);
originBool = BoolExpression.CreateOr(originBool, BoolExpression.CreateLiteral(boolExpr, RightDomainMap));
}
}
// Qualify the slotNum with the child.CqlAlias for the THEN
QualifiedSlot slot = child.QualifySlotWithBlockAlias(slotNum);
caseForOuterJoins.AddWhenThen(originBool, slot);
}
// requires: The CellConstantDomains in the OneOfConsts of the where
// clause are partially done
// effects: Given the domains of different variables in domainMap,
// fixes the whereClause of this such that all the
// CellConstantDomains in OneOfConsts are complete
internal void UpdateWhereClause(MemberDomainMap domainMap)
{
List <BoolExpression> atoms = new List <BoolExpression>();
foreach (BoolExpression atom in WhereClause.Atoms)
{
BoolLiteral literal = atom.AsLiteral;
MemberRestriction restriction = literal as MemberRestriction;
Debug.Assert(restriction != null, "All bool literals must be OneOfConst at this point");
// The oneOfConst needs to be fixed with the new possible values from the domainMap.
IEnumerable <Constant> possibleValues = domainMap.GetDomain(restriction.RestrictedMemberSlot.MemberPath);
MemberRestriction newOneOf = restriction.CreateCompleteMemberRestriction(possibleValues);
// Prevent optimization of single constraint e.g: "300 in (300)"
// But we want to optimize type constants e.g: "category in (Category)"
// To prevent optimization of bool expressions we add a Sentinel OneOF
ScalarRestriction scalarConst = restriction as ScalarRestriction;
bool addSentinel =
scalarConst != null &&
!scalarConst.Domain.Contains(Constant.Null) &&
!scalarConst.Domain.Contains(Constant.NotNull) &&
!scalarConst.Domain.Contains(Constant.Undefined);
if (addSentinel)
{
domainMap.AddSentinel(newOneOf.RestrictedMemberSlot.MemberPath);
}
atoms.Add(BoolExpression.CreateLiteral(newOneOf, domainMap));
if (addSentinel)
{
domainMap.RemoveSentinel(newOneOf.RestrictedMemberSlot.MemberPath);
}
}
// We create a new whereClause that has the memberDomainMap set
if (atoms.Count > 0)
{
m_whereClause = BoolExpression.CreateAnd(atoms.ToArray());
}
}
