// effects: Checks for key constraint implication problems from
// leftViewConstraints to rightViewConstraints. Adds errors/warning to m_errorLog
private void CheckImplicationKeyConstraints(
ViewSchemaConstraints leftViewConstraints,
ViewSchemaConstraints rightViewConstraints)
{
// if cImpliesS is true, every rightKeyConstraint must be implied
// if it is false, at least one key constraint for each C-level
// extent must be implied
foreach (var rightKeyConstraint in rightViewConstraints.KeyConstraints)
{
// Go through all the left Side constraints and check for implication
var found = false;
foreach (var leftKeyConstraint in leftViewConstraints.KeyConstraints)
{
if (leftKeyConstraint.Implies(rightKeyConstraint))
{
found = true;
break; // The implication holds - so no problem
}
}
if (false == found)
{
// No C-side key constraint implies this S-level key constraint
// Report a problem
m_errorLog.AddEntry(ViewKeyConstraint.GetErrorRecord(rightKeyConstraint));
}
}
}
private void CheckImplication(
SchemaConstraints <ViewKeyConstraint> cViewConstraints,
SchemaConstraints <ViewKeyConstraint> sViewConstraints)
{
this.CheckImplicationKeyConstraints(cViewConstraints, sViewConstraints);
KeyToListMap <CellGroupValidator.ExtentPair, ViewKeyConstraint> keyToListMap = new KeyToListMap <CellGroupValidator.ExtentPair, ViewKeyConstraint>((IEqualityComparer <CellGroupValidator.ExtentPair>)EqualityComparer <CellGroupValidator.ExtentPair> .Default);
foreach (ViewKeyConstraint keyConstraint in cViewConstraints.KeyConstraints)
{
CellGroupValidator.ExtentPair key = new CellGroupValidator.ExtentPair(keyConstraint.Cell.CQuery.Extent, keyConstraint.Cell.SQuery.Extent);
keyToListMap.Add(key, keyConstraint);
}
foreach (CellGroupValidator.ExtentPair key in keyToListMap.Keys)
{
ReadOnlyCollection <ViewKeyConstraint> readOnlyCollection = keyToListMap.ListForKey(key);
bool flag = false;
foreach (ViewKeyConstraint second in readOnlyCollection)
{
foreach (ViewKeyConstraint keyConstraint in sViewConstraints.KeyConstraints)
{
if (keyConstraint.Implies(second))
{
flag = true;
break;
}
}
}
if (!flag)
{
this.m_errorLog.AddEntry(ViewKeyConstraint.GetErrorRecord((IEnumerable <ViewKeyConstraint>)readOnlyCollection));
}
}
}
private static SchemaConstraints <ViewKeyConstraint> PropagateConstraints(
SchemaConstraints <BasicKeyConstraint> baseConstraints)
{
SchemaConstraints <ViewKeyConstraint> schemaConstraints = new SchemaConstraints <ViewKeyConstraint>();
foreach (BasicKeyConstraint keyConstraint in baseConstraints.KeyConstraints)
{
ViewKeyConstraint constraint = keyConstraint.Propagate();
if (constraint != null)
{
schemaConstraints.Add(constraint);
}
}
return(schemaConstraints);
}
// effects: Propagates baseConstraints derived from the cellrelations
// to the corresponding viewCellRelations and returns the list of
// propagated constraints
private static ViewSchemaConstraints PropagateConstraints(BasicSchemaConstraints baseConstraints)
{
ViewSchemaConstraints propagatedConstraints = new ViewSchemaConstraints();
// Key constraint propagation
foreach (BasicKeyConstraint keyConstraint in baseConstraints.KeyConstraints)
{
ViewKeyConstraint viewConstraint = keyConstraint.Propagate();
if (viewConstraint != null)
{
propagatedConstraints.Add(viewConstraint);
}
}
return(propagatedConstraints);
}
// effects: Checks if all sViewConstraints are implied by the
// constraints in cViewConstraints. If some S-level constraints are
// not implied, adds errors/warnings to m_errorLog
private void CheckImplication(ViewSchemaConstraints cViewConstraints, ViewSchemaConstraints sViewConstraints)
{
// Check key constraints
// i.e., if S has a key <k1, k2>, C must have a key that is a subset of this
CheckImplicationKeyConstraints(cViewConstraints, sViewConstraints);
// For updates, we need to ensure the following: for every
// extent E, table T pair, some key of E is implied by T's key
// Get all key constraints for each extent and each table
var extentPairConstraints =
new KeyToListMap <ExtentPair, ViewKeyConstraint>(EqualityComparer <ExtentPair> .Default);
foreach (var cKeyConstraint in cViewConstraints.KeyConstraints)
{
var pair = new ExtentPair(cKeyConstraint.Cell.CQuery.Extent, cKeyConstraint.Cell.SQuery.Extent);
extentPairConstraints.Add(pair, cKeyConstraint);
}
// Now check that we guarantee at least one constraint per
// extent/table pair
foreach (var extentPair in extentPairConstraints.Keys)
{
var cKeyConstraints = extentPairConstraints.ListForKey(extentPair);
var sImpliesSomeC = false;
// Go through all key constraints for the extent/table pair, and find one that S implies
foreach (var cKeyConstraint in cKeyConstraints)
{
foreach (var sKeyConstraint in sViewConstraints.KeyConstraints)
{
if (sKeyConstraint.Implies(cKeyConstraint))
{
sImpliesSomeC = true;
break; // The implication holds - so no problem
}
}
}
if (sImpliesSomeC == false)
{
// Indicate that at least one key must be ensured on the S-side
m_errorLog.AddEntry(ViewKeyConstraint.GetErrorRecord(cKeyConstraints));
}
}
}
private void CheckImplicationKeyConstraints(
SchemaConstraints <ViewKeyConstraint> leftViewConstraints,
SchemaConstraints <ViewKeyConstraint> rightViewConstraints)
{
foreach (ViewKeyConstraint keyConstraint1 in rightViewConstraints.KeyConstraints)
{
bool flag = false;
foreach (ViewKeyConstraint keyConstraint2 in leftViewConstraints.KeyConstraints)
{
if (keyConstraint2.Implies(keyConstraint1))
{
flag = true;
break;
}
}
if (!flag)
{
this.m_errorLog.AddEntry(ViewKeyConstraint.GetErrorRecord(keyConstraint1));
}
}
}
