private EquivalenceClassForSymmetricEGD createEquivalenceClass(Dependency egd) {
FormulaVariable v1 =
((ComparisonAtom) egd.getConclusion().getAtoms().get(0)).getVariables().get(0);
AttributeRef variableOccurrence = v1.getPremiseRelationalOccurrences().get(0).getAttributeRef();
AttributeRef conclusionAttribute =
EquivalenceClassUtility.correctAttributeForSymmetricEGDs(variableOccurrence, egd);
List<BackwardAttribute> attributesForBackwardChasing = findAttributesForBackwardChasing(egd);
return new EquivalenceClassForSymmetricEGD(
egd, conclusionAttribute, attributesForBackwardChasing);
}
public static List<AttributeRef> extractRequestedAttributesWithExistential(
Dependency dependency) {
List<AttributeRef> result = new ArrayList<AttributeRef>();
result.addAll(dependency.getQueriedAttributes());
for (FormulaVariable variable : dependency.getConclusion().getLocalVariables()) {
if (variable.getConclusionRelationalOccurrences().size() == 1) {
continue;
}
for (FormulaVariableOccurrence occurrence : variable.getConclusionRelationalOccurrences()) {
if (logger.isTraceEnabled()) logger.trace("Inspecting occurrence: " + occurrence);
AttributeRef attribute = occurrence.getAttributeRef();
AttributeRef unaliasedAttribute = ChaseUtility.unAlias(attribute);
LunaticUtility.addIfNotContained(result, unaliasedAttribute);
}
}
for (AttributeRef attributeRef : dependency.getAdditionalAttributes()) {
if (!result.contains(attributeRef)) {
result.add(attributeRef);
}
}
return result;
}
public static List<FormulaVariable> getExistentialVariables(Dependency dependency) {
return dependency.getConclusion().getLocalVariables();
}
