Examples with FunctionalDependency org.apache.hyracks.algebricks.core.algebra.properties.FunctionalDependency used on opensource projects

Example 26 with FunctionalDependency

use of org.apache.hyracks.algebricks.core.algebra.properties.FunctionalDependency in project asterixdb by apache.

the class FDsAndEquivClassesVisitor method visitGroupByOperator.

@Override
public Void visitGroupByOperator(GroupByOperator op, IOptimizationContext ctx) throws AlgebricksException {
    Map<LogicalVariable, EquivalenceClass> equivalenceClasses = new HashMap<LogicalVariable, EquivalenceClass>();
    List<FunctionalDependency> functionalDependencies = new ArrayList<FunctionalDependency>();
    ctx.putEquivalenceClassMap(op, equivalenceClasses);
    ctx.putFDList(op, functionalDependencies);
    List<FunctionalDependency> inheritedFDs = new ArrayList<FunctionalDependency>();
    for (ILogicalPlan p : op.getNestedPlans()) {
        for (Mutable<ILogicalOperator> r : p.getRoots()) {
            ILogicalOperator op2 = r.getValue();
            equivalenceClasses.putAll(getOrComputeEqClasses(op2, ctx));
            inheritedFDs.addAll(getOrComputeFDs(op2, ctx));
        }
    }
    ILogicalOperator op0 = op.getInputs().get(0).getValue();
    inheritedFDs.addAll(getOrComputeFDs(op0, ctx));
    Map<LogicalVariable, EquivalenceClass> inheritedEcs = getOrComputeEqClasses(op0, ctx);
    for (FunctionalDependency inherited : inheritedFDs) {
        boolean isCoveredByGbyOrDecorVars = true;
        List<LogicalVariable> newHead = new ArrayList<LogicalVariable>(inherited.getHead().size());
        for (LogicalVariable v : inherited.getHead()) {
            LogicalVariable vnew = getNewGbyVar(op, v);
            if (vnew == null) {
                vnew = getNewDecorVar(op, v);
                if (vnew == null) {
                    isCoveredByGbyOrDecorVars = false;
                }
                break;
            }
            newHead.add(vnew);
        }
        if (isCoveredByGbyOrDecorVars) {
            List<LogicalVariable> newTail = new ArrayList<LogicalVariable>();
            for (LogicalVariable v2 : inherited.getTail()) {
                LogicalVariable v3 = getNewGbyVar(op, v2);
                if (v3 != null) {
                    newTail.add(v3);
                }
            }
            if (!newTail.isEmpty()) {
                FunctionalDependency newFd = new FunctionalDependency(newHead, newTail);
                functionalDependencies.add(newFd);
            }
        }
    }
    List<LogicalVariable> premiseGby = new LinkedList<LogicalVariable>();
    List<Pair<LogicalVariable, Mutable<ILogicalExpression>>> gByList = op.getGroupByList();
    for (Pair<LogicalVariable, Mutable<ILogicalExpression>> p : gByList) {
        premiseGby.add(p.first);
    }
    List<Pair<LogicalVariable, Mutable<ILogicalExpression>>> decorList = op.getDecorList();
    LinkedList<LogicalVariable> conclDecor = new LinkedList<LogicalVariable>();
    for (Pair<LogicalVariable, Mutable<ILogicalExpression>> p : decorList) {
        conclDecor.add(GroupByOperator.getDecorVariable(p));
    }
    if (!conclDecor.isEmpty()) {
        functionalDependencies.add(new FunctionalDependency(premiseGby, conclDecor));
    }
    Set<LogicalVariable> gbySet = new HashSet<LogicalVariable>();
    for (Pair<LogicalVariable, Mutable<ILogicalExpression>> p : gByList) {
        ILogicalExpression expr = p.second.getValue();
        if (expr.getExpressionTag() == LogicalExpressionTag.VARIABLE) {
            VariableReferenceExpression v = (VariableReferenceExpression) expr;
            gbySet.add(v.getVariableReference());
        }
    }
    LocalGroupingProperty lgp = new LocalGroupingProperty(gbySet);
    ILocalStructuralProperty normalizedLgp = lgp.normalize(inheritedEcs, inheritedFDs);
    Set<LogicalVariable> normSet = new ListSet<>();
    normalizedLgp.getColumns(normSet);
    List<Pair<LogicalVariable, Mutable<ILogicalExpression>>> newGbyList = new ArrayList<>();
    boolean changed = false;
    for (Pair<LogicalVariable, Mutable<ILogicalExpression>> p : gByList) {
        ILogicalExpression expr = p.second.getValue();
        if (expr.getExpressionTag() == LogicalExpressionTag.VARIABLE) {
            VariableReferenceExpression varRef = (VariableReferenceExpression) expr;
            LogicalVariable v2 = varRef.getVariableReference();
            EquivalenceClass ec2 = inheritedEcs.get(v2);
            LogicalVariable v3;
            if (ec2 != null && !ec2.representativeIsConst()) {
                v3 = ec2.getVariableRepresentative();
            } else {
                v3 = v2;
            }
            if (normSet.contains(v3)) {
                newGbyList.add(p);
            } else {
                changed = true;
                decorList.add(p);
            }
        } else {
            newGbyList.add(p);
        }
    }
    if (changed) {
        AlgebricksConfig.ALGEBRICKS_LOGGER.fine(">>>> Group-by list changed from " + GroupByOperator.veListToString(gByList) + " to " + GroupByOperator.veListToString(newGbyList) + ".\n");
    }
    gByList.clear();
    gByList.addAll(newGbyList);
    return null;
}

Example 27 with FunctionalDependency

use of org.apache.hyracks.algebricks.core.algebra.properties.FunctionalDependency in project asterixdb by apache.

the class AbstractFunctionCallExpression method getFDsAndEquivClassesForEqWithConstant.

private static final void getFDsAndEquivClassesForEqWithConstant(ConstantExpression c, VariableReferenceExpression v, Collection<FunctionalDependency> fds, Map<LogicalVariable, EquivalenceClass> equivClasses) {
    LogicalVariable var = v.getVariableReference();
    LinkedList<LogicalVariable> head = new LinkedList<LogicalVariable>();
    // empty set in the head
    LinkedList<LogicalVariable> tail = new LinkedList<LogicalVariable>();
    tail.add(var);
    FunctionalDependency fd = new FunctionalDependency(head, tail);
    fds.add(fd);
    EquivalenceClass ec = equivClasses.get(var);
    if (ec == null) {
        LinkedList<LogicalVariable> members = new LinkedList<LogicalVariable>();
        members.add(var);
        EquivalenceClass eclass = new EquivalenceClass(members, c);
        equivClasses.put(var, eclass);
    } else {
        if (ec.representativeIsConst()) {
            ILogicalExpression c1 = ec.getConstRepresentative();
            if (!c1.equals(c)) {
                // here I could also rewrite to FALSE
                return;
            }
        }
        ec.setConstRepresentative(c);
    }
}

Example 28 with FunctionalDependency

use of org.apache.hyracks.algebricks.core.algebra.properties.FunctionalDependency in project asterixdb by apache.

the class AbstractFunctionCallExpression method getFDsAndEquivClassesForColumnEq.

/*
     * Obs.: mgmt. of equiv. classes should use a more efficient data
     * structure,if we are to implem. cost-bazed optim.
     */
private static final void getFDsAndEquivClassesForColumnEq(VariableReferenceExpression v1, VariableReferenceExpression v2, Collection<FunctionalDependency> fds, Map<LogicalVariable, EquivalenceClass> equivClasses) {
    LogicalVariable var1 = v1.getVariableReference();
    LogicalVariable var2 = v2.getVariableReference();
    LinkedList<LogicalVariable> set1 = new LinkedList<LogicalVariable>();
    set1.add(var1);
    LinkedList<LogicalVariable> set2 = new LinkedList<LogicalVariable>();
    set2.add(var2);
    FunctionalDependency fd1 = new FunctionalDependency(set1, set2);
    FunctionalDependency fd2 = new FunctionalDependency(set2, set1);
    fds.add(fd1);
    fds.add(fd2);
    EquivalenceClass ec1 = equivClasses.get(var1);
    EquivalenceClass ec2 = equivClasses.get(var2);
    if (ec1 == null && ec2 == null) {
        LinkedList<LogicalVariable> members = new LinkedList<LogicalVariable>();
        members.add(var1);
        members.add(var2);
        EquivalenceClass ec = new EquivalenceClass(members, var1);
        equivClasses.put(var1, ec);
        equivClasses.put(var2, ec);
    } else if (ec1 == null && ec2 != null) {
        ec2.addMember(var1);
        equivClasses.put(var1, ec2);
    } else if (ec2 == null && ec1 != null) {
        ec1.addMember(var2);
        equivClasses.put(var2, ec1);
    } else {
        ec1.merge(ec2);
        for (LogicalVariable w : equivClasses.keySet()) {
            if (ec2.getMembers().contains(w)) {
                equivClasses.put(w, ec1);
            }
        }
    }
}

Example 29 with FunctionalDependency

use of org.apache.hyracks.algebricks.core.algebra.properties.FunctionalDependency in project asterixdb by apache.

the class DataSource method computeFDs.

@Override
public void computeFDs(List<LogicalVariable> scanVariables, List<FunctionalDependency> fdList) {
    int n = scanVariables.size();
    if (n > 1) {
        List<LogicalVariable> head = new ArrayList<>(scanVariables.subList(0, n - 1));
        List<LogicalVariable> tail = new ArrayList<>(1);
        tail.addAll(scanVariables);
        FunctionalDependency fd = new FunctionalDependency(head, tail);
        fdList.add(fd);
    }
}