public override List <Tuple <MatchNode, MatchEdge, List <MatchEdge>, List <MatchEdge>, List <MatchEdge> > > GetOptimizedTraversalOrder(ConnectedComponent subGraph)
{
if (subGraph.Nodes.Count == 1)
{
return
(this.GenerateTraversalOrderFromTraversalChain(
new List <Tuple <MatchNode, MatchEdge, MatchNode, List <MatchEdge>, List <MatchEdge> > >
{
new Tuple <MatchNode, MatchEdge, MatchNode, List <MatchEdge>, List <MatchEdge> >(
subGraph.Nodes.First().Value, null, null, null, null)
}));
}
// If it exists, pick a node without incoming edges as the start point
List <MatchComponent> componentStates = subGraph.Nodes.Where(node => node.Value.ReverseNeighbors.Count == 0).
Select(node => new MatchComponent(node.Value)).Take(1).ToList();
// Otherwise, pick a node randomly as the start point
if (!componentStates.Any())
{
componentStates.Add(new MatchComponent(subGraph.Nodes.First().Value));
}
// DP
while (componentStates.Any())
{
List <MatchComponent> nextCompnentStates = new List <MatchComponent>();
// Iterate on current components
foreach (MatchComponent curComponent in componentStates)
{
OneHeightTree nodeUnits = this.GetNodeUnits(subGraph, curComponent);
if (nodeUnits == null &&
curComponent.ActiveNodeCount == subGraph.ActiveNodeCount &&
curComponent.EdgeMaterilizedDict.Count(e => e.Value == true) == subGraph.Edges.Count(e => e.Value.IsDanglingEdge == false))
{
return(this.GenerateTraversalOrderFromTraversalChain(curComponent.TraversalChain));
}
CandidateJoinUnit candidateUnit = this.GetCandidateUnits2(nodeUnits, curComponent);
// Add it to the current component to generate next states
MatchComponent newComponent = this.GetNextState(curComponent, candidateUnit);
if (nextCompnentStates.Count >= MaxStates)
{
throw new GraphViewException("This graph pattern is not supported yet.");
}
nextCompnentStates.Add(newComponent);
}
componentStates = nextCompnentStates;
}
return(null);
}
/// <summary>
/// Transit from current component to the new component in the next state given the Node Unit
/// </summary>
/// <param name="candidateTree"></param>
/// <param name="densityDict"></param>
/// <param name="subGraph"></param>
/// <param name="statisticsCalculator"></param>
/// <returns></returns>
public MatchComponent GetNextState(
OneHeightTree candidateTree,
Dictionary <string, double> densityDict,
IMatchJoinStatisticsCalculator statisticsCalculator)
{
var newComponent = new MatchComponent(this);
var root = candidateTree.TreeRoot;
WBooleanExpression joinCondition = null;
string nodeName = "";
// Update Nodes
if (newComponent.MaterializedNodeSplitCount.ContainsKey(root))
{
newComponent.MaterializedNodeSplitCount[root]++;
nodeName = newComponent.GetNodeRefName(root);
joinCondition = new WBooleanComparisonExpression
{
FirstExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {
Value = root.RefAlias
},
new Identifier {
Value = "GlobalNodeId"
}
),
},
SecondExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {
Value = nodeName
},
new Identifier {
Value = "GlobalNodeId"
}
),
},
ComparisonType = BooleanComparisonType.Equals
};
}
else
{
nodeName = root.RefAlias;
newComponent.Nodes.Add(root);
newComponent.MaterializedNodeSplitCount[root] = 0;
newComponent.StatisticsDict[root] = new ColumnStatistics {
Selectivity = 1.0 / root.TableRowCount
};
}
// Constructs table reference
WTableReference nodeTable = new WNamedTableReference
{
Alias = new Identifier {
Value = nodeName
},
TableObjectName = root.TableObjectName
};
WTableReference compTable = newComponent.TableRef;
// Updates join conditions
double selectivity = 1.0;
double degrees = 1.0;
var DensityCount = new Dictionary <string, int>(StringComparer.CurrentCultureIgnoreCase);
List <MatchEdge> inEdges;
if (newComponent.UnmaterializedNodeMapping.TryGetValue(root, out inEdges))
{
var firstEdge = inEdges.First();
bool materialized = newComponent.EdgeMaterilizedDict[firstEdge];
newComponent.UnmaterializedNodeMapping.Remove(root);
selectivity *= 1.0 / root.TableRowCount;
// Component materialized edge to root
if (materialized)
{
joinCondition = WBooleanBinaryExpression.Conjunction(joinCondition, new WBooleanComparisonExpression
{
FirstExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {
Value = firstEdge.EdgeAlias
},
new Identifier {
Value = "Sink"
}
),
},
SecondExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {
Value = nodeName
},
new Identifier {
Value = "GlobalNodeId"
}
)
},
ComparisonType = BooleanComparisonType.Equals
});
//var statistics = ColumnStatistics.UpdateHistogram(newComponent.StatisticsDict[root],
// new ColumnStatistics {Selectivity = 1.0/root.TableRowCount});
//selectivity *= statistics.Selectivity;
//newComponent.StatisticsDict[root] = statistics;
if (DensityCount.ContainsKey(root.TableObjectName.ToString()))
{
DensityCount[root.TableObjectName.ToString()]++;
}
else
{
DensityCount[root.TableObjectName.ToString()] = 1;
}
}
// Component unmaterialized edge to root
else
{
ColumnStatistics statistics = null;
foreach (var edge in inEdges)
{
// Update component table
compTable = SpanTableRef(compTable, edge, newComponent.GetNodeRefName(edge.SourceNode));
newComponent.EdgeMaterilizedDict[edge] = true;
joinCondition = WBooleanBinaryExpression.Conjunction(joinCondition,
new WBooleanComparisonExpression
{
FirstExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {
Value = edge.EdgeAlias
},
new Identifier {
Value = "Sink"
}
),
},
SecondExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {
Value = nodeName
},
new Identifier {
Value = "GlobalNodeId"
}
)
},
ComparisonType = BooleanComparisonType.Equals
});
statistics = ColumnStatistics.UpdateHistogram(statistics,
newComponent.Context.GetEdgeStatistics(edge));
selectivity *= statistics.Selectivity;
}
newComponent.StatisticsDict[root] = statistics;
if (DensityCount.ContainsKey(root.TableObjectName.ToString()))
{
DensityCount[root.TableObjectName.ToString()] += inEdges.Count;
}
else
{
DensityCount[root.TableObjectName.ToString()] = inEdges.Count;
}
}
}
var jointEdges = candidateTree.MaterializedEdges;
int sinkToSinkCount = 0;
foreach (var jointEdge in jointEdges)
{
// Update node table
nodeTable = SpanTableRef(nodeTable, jointEdge, nodeName);
degrees *= jointEdge.AverageDegree;
newComponent.EdgeMaterilizedDict[jointEdge] = true;
var sinkNode = jointEdge.SinkNode;
// Leaf to component materialized node
if (newComponent.MaterializedNodeSplitCount.ContainsKey(sinkNode))
{
joinCondition = WBooleanBinaryExpression.Conjunction(joinCondition,
new WBooleanComparisonExpression
{
FirstExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {
Value = jointEdge.EdgeAlias
},
new Identifier {
Value = "Sink"
}
),
},
SecondExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {
Value = sinkNode.RefAlias
},
new Identifier {
Value = "GlobalNodeId"
}
)
},
ComparisonType = BooleanComparisonType.Equals
});
var statistics = ColumnStatistics.UpdateHistogram(newComponent.StatisticsDict[sinkNode],
newComponent.Context.GetEdgeStatistics(jointEdge));
selectivity *= statistics.Selectivity;
newComponent.StatisticsDict[sinkNode] = statistics;
if (DensityCount.ContainsKey(sinkNode.TableObjectName.ToString()))
{
DensityCount[sinkNode.TableObjectName.ToString()]++;
}
else
{
DensityCount[sinkNode.TableObjectName.ToString()] = 1;
}
}
// Leaf to component unmaterialized node
else
{
inEdges = newComponent.UnmaterializedNodeMapping[sinkNode];
var firstEdge = inEdges.First();
bool materlizedEdge = newComponent.EdgeMaterilizedDict[firstEdge];
// Leaf to materialized leaf
if (materlizedEdge)
{
joinCondition = WBooleanBinaryExpression.Conjunction(joinCondition,
new WBooleanComparisonExpression
{
FirstExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {
Value = jointEdge.EdgeAlias
},
new Identifier {
Value = "Sink"
}
),
},
SecondExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {
Value = firstEdge.EdgeAlias
},
new Identifier {
Value = "Sink"
}
)
},
ComparisonType = BooleanComparisonType.Equals
});
sinkToSinkCount++;
var statistics = ColumnStatistics.UpdateHistogram(newComponent.StatisticsDict[sinkNode],
newComponent.Context.GetEdgeStatistics(jointEdge));
selectivity *= statistics.Selectivity;
newComponent.StatisticsDict[sinkNode] = statistics;
}
// Leaf to unmaterialized leaf
else
{
ColumnStatistics compSinkNodeStatistics = null;
foreach (var inEdge in inEdges)
{
compTable = SpanTableRef(compTable, inEdge, newComponent.GetNodeRefName(inEdge.SourceNode));
newComponent.EdgeMaterilizedDict[inEdge] = true;
joinCondition = WBooleanBinaryExpression.Conjunction(joinCondition,
new WBooleanComparisonExpression
{
FirstExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {
Value = jointEdge.EdgeAlias
},
new Identifier {
Value = "Sink"
}
),
},
SecondExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {
Value = inEdge.EdgeAlias
},
new Identifier {
Value = "Sink"
}
)
},
ComparisonType = BooleanComparisonType.Equals
});
sinkToSinkCount++;
var leafToLeafStatistics = statisticsCalculator.GetLeafToLeafStatistics(jointEdge, inEdge);
selectivity *= leafToLeafStatistics.Selectivity;
compSinkNodeStatistics =
ColumnStatistics.UpdateHistogram(compSinkNodeStatistics,
newComponent.Context.GetEdgeStatistics(inEdge));
}
newComponent.StatisticsDict[sinkNode] = compSinkNodeStatistics;
}
}
}
var unmatEdges = candidateTree.UnmaterializedEdges;
foreach (var unmatEdge in unmatEdges)
{
newComponent.EdgeMaterilizedDict[unmatEdge] = false;
newComponent.Nodes.Add(unmatEdge.SinkNode);
var sinkNodeInEdges = newComponent.UnmaterializedNodeMapping.GetOrCreate(unmatEdge.SinkNode);
sinkNodeInEdges.Add(unmatEdge);
degrees *= unmatEdge.AverageDegree;
}
// Calculate Estimated Join Selectivity & Estimated Node Size
double estimatedSelectity = 1.0;
int count = 0;
bool sinkJoin = false;
foreach (var item in densityDict.Where(e => DensityCount.ContainsKey(e.Key)))
{
var density = item.Value;
var curJoinCount = DensityCount[item.Key];
var curJoinSelectitivy = Math.Pow(density, 2 - Math.Pow(2, 1 - curJoinCount));
if (!sinkJoin && ColumnStatistics.DefaultDensity < density)
{
var curSinkJoinSelectivity = Math.Pow(ColumnStatistics.DefaultDensity,
2 - Math.Pow(2, 1 - sinkToSinkCount));
estimatedSelectity *= Math.Pow(curSinkJoinSelectivity, Math.Pow(2, -count));
count += sinkToSinkCount;
sinkJoin = true;
}
estimatedSelectity *= Math.Pow(curJoinSelectitivy, Math.Pow(2, -count));
count += curJoinCount;
}
var estimatedNodeUnitSize = root.EstimatedRows *
Math.Pow(1000, candidateTree.MaterializedEdges.Count + candidateTree.UnmaterializedEdges.Count);
// Update Table Reference
newComponent.TableRef = GetPlanAndUpdateCost(candidateTree, newComponent, nodeTable, compTable, joinCondition,
degrees, selectivity, estimatedNodeUnitSize, estimatedSelectity);
return(newComponent);
}
/// <summary>
/// Calculate join costs and update components using optimal join method & order
/// </summary>
/// <param name="nodeUnitCandidate"></param>
/// <param name="component"></param>
/// <param name="nodeTable"></param>
/// <param name="componentTable"></param>
/// <param name="joinCondition"></param>
/// <param name="nodeDegrees"></param>
/// <param name="estimatedNodeUnitSize"></param>
/// <param name="estimatedSelectivity"></param>
/// <returns></returns>
private static WTableReference GetPlanAndUpdateCost(
OneHeightTree nodeUnitCandidate,
MatchComponent component,
WTableReference nodeTable,
WTableReference componentTable,
WBooleanExpression joinCondition,
double nodeDegrees,
double joinSelectivity,
double estimatedNodeUnitSize,
double estimatedSelectivity)
{
var nodeUnitSize = nodeUnitCandidate.TreeRoot.EstimatedRows * nodeDegrees;
var componentSize = component.Size;
var estimatedCompSize = component.EstimateSize;
var cost = nodeUnitSize + componentSize;
//var joinSelectivity =
// nodeWithJoinMapping.SelectivityProduct;
//nodeWithJoinMapping.ExponentialSelevtivityProduct;
WQualifiedJoin joinTable = new WQualifiedJoin
{
FirstTableRef = componentTable,
SecondTableRef = nodeTable,
JoinCondition = joinCondition,
QualifiedJoinType = QualifiedJoinType.Inner,
JoinHint = JoinHint.Hash
};
var node = nodeUnitCandidate.TreeRoot;
// If the node is already in the component, then only multiply the degree to get the size
double nodeUnitActualSize;
if (component.MaterializedNodeSplitCount[node] > 0)
{
nodeUnitActualSize = nodeDegrees;
var cEstEdge = Math.Pow(1000, component.EdgeMaterilizedDict.Count(e => !e.Value));
var cSize = component.EstimateSize / cEstEdge;
var nSize = node.EstimatedRows;
if (nSize > cSize)
{
component.EstimateSize = estimatedNodeUnitSize * cEstEdge * estimatedSelectivity;
}
else
{
component.EstimateSize = component.EstimateSize * Math.Pow(1000, nodeUnitCandidate.UnmaterializedEdges.Count) *
estimatedSelectivity;
}
}
else
{
nodeUnitActualSize = nodeUnitSize;
component.EstimateSize *= estimatedNodeUnitSize * estimatedSelectivity;
}
//Update Size
component.Size *= nodeUnitActualSize * joinSelectivity;
// Update Cost
component.Cost += cost;
// Debug
#if DEBUG
//Trace.Write(component.NodeUnits.Count+" ");
//foreach (var n in component.NodeUnits.Where(e => e.Key != node.Node.ExposedName))
//{
// Trace.Write(n.Value.NodeRefName);
//}
//Trace.Write(component.NodeUnits[node.Node.ExposedName].NodeRefName+" ");
//Trace.Write(" "+(long)component.Cost+" "+(long)component.Size);
//Trace.Write(" ");
//foreach (var item in component.PopulatedEdgesName)
//{
// Trace.Write(item + " ");
//}
//Trace.Write("; ");
//foreach (var unpopulatedEdge in component.UnpopulatedEdges)
//{
// Trace.Write(unpopulatedEdge.Alias + " ");
//}
//Trace.WriteLine("");
#endif
// Update TableRef
// Only consider the size in the first join
if (component.MaterializedNodeSplitCount.Count == 2 && component.MaterializedNodeSplitCount.All(e => e.Value == 0))
{
var nodeInComp = component.MaterializedNodeSplitCount.Keys.First(e => e != node);
if (nodeUnitSize < componentSize)
{
joinTable.FirstTableRef = nodeTable;
joinTable.SecondTableRef = componentTable;
component.TotalMemory = component.DeltaMemory = nodeUnitSize;
component.EstimateTotalMemory = component.EstimateDeltaMemory = estimatedNodeUnitSize;
component.RightestTableRefSize = nodeInComp.EstimatedRows;
component.FatherOfRightestTableRef = new Tuple <WQualifiedJoin, String>(joinTable,
component.GetNodeRefName(nodeInComp));
AdjustEstimation(component, nodeTable, joinTable, nodeUnitSize, estimatedNodeUnitSize,
nodeUnitCandidate.TreeRoot.EstimatedRows, new Tuple <WQualifiedJoin, string>(joinTable, component.GetNodeRefName(node)));
}
else
{
component.TotalMemory = component.DeltaMemory = componentSize;
component.EstimateTotalMemory = component.EstimateDeltaMemory = component.EstimateSize;
component.RightestTableRefSize = nodeUnitCandidate.TreeRoot.EstimatedRows;
component.FatherOfRightestTableRef = new Tuple <WQualifiedJoin, String>(joinTable, component.GetNodeRefName(node));
AdjustEstimation(component, componentTable, joinTable, componentSize, estimatedCompSize,
nodeInComp.EstimatedRows, new Tuple <WQualifiedJoin, string>(joinTable, component.GetNodeRefName(nodeInComp)));
}
}
else
{
double sizeFactor = 5;//1000;
double maxMemory = 1e8;
double loopJoinInnerThreshold = 10000;
double loopJoinOuterThreshold = 1000000;
// Left Deep
if (componentSize * sizeFactor < nodeUnitSize)
{
var curDeltaMemory = componentSize;
component.TotalMemory = component.DeltaMemory + curDeltaMemory;
component.DeltaMemory = curDeltaMemory;
var curDeltaEstimateMemory = component.EstimateSize;
component.EstimateTotalMemory = component.EstimateDeltaMemory + curDeltaEstimateMemory;
component.EstimateDeltaMemory = curDeltaEstimateMemory;
// Adjust estimation in sql server
AdjustEstimation(component, componentTable, joinTable, componentSize, estimatedCompSize,
component.RightestTableRefSize, component.FatherOfRightestTableRef);
component.FatherOfRightestTableRef = new Tuple <WQualifiedJoin, string>(joinTable, component.GetNodeRefName(node));
component.RightestTableRefSize = nodeUnitCandidate.TreeRoot.EstimatedRows;
}
else
{
// Loop Join
if (
//((nodeUnitSize < loopJoinInnerThreshold /*&& componentSize < loopJoinOuterThreshold*/) || component.DeltaMemory + componentSize > maxMemory / 100) &&
((nodeUnitSize < loopJoinInnerThreshold && componentSize < loopJoinOuterThreshold) ||
component.DeltaMemory + componentSize > maxMemory) &&
nodeUnitCandidate.MaterializedEdges.Count == 0)
{
component.TotalMemory = component.DeltaMemory;
component.EstimateTotalMemory = component.EstimateDeltaMemory;
joinTable.JoinHint = JoinHint.Loop;
component.EstimateSize = estimatedCompSize * estimatedNodeUnitSize /
nodeUnitCandidate.TreeRoot.TableRowCount;
}
// Right Deep
else
{
joinTable.FirstTableRef = nodeTable;
joinTable.SecondTableRef = componentTable;
AdjustEstimation(component, nodeTable, joinTable, nodeUnitSize, estimatedNodeUnitSize,
node.EstimatedRows, new Tuple <WQualifiedJoin, string>(joinTable, component.GetNodeRefName(node)));
component.TotalMemory += nodeUnitSize;
component.DeltaMemory = component.TotalMemory;
component.EstimateTotalMemory += estimatedNodeUnitSize;
component.EstimateDeltaMemory = component.EstimateTotalMemory;
}
}
}
return(new WParenthesisTableReference
{
Table = joinTable
});
}
private CandidateJoinUnit GetCandidateUnits2(OneHeightTree tree, MatchComponent component)
{
var revEdgeDict = Graph.ReversedEdgeDict;
var root = tree.TreeRoot;
List <MatchEdge> inEdges;
component.UnmaterializedNodeMapping.TryGetValue(root, out inEdges);
var outEdges = new List <MatchEdge>();
var unpopEdges = new List <MatchEdge>();
foreach (var edge in tree.Edges)
{
if (component.Nodes.Contains(edge.SinkNode))
{
outEdges.Add(edge);
}
else
{
unpopEdges.Add(edge);
}
}
var rawEdges = new Dictionary <string, Tuple <MatchEdge, EdgeDir> >();
var extInEdges = new Dictionary <string, MatchEdge>();
if (inEdges != null)
{
rawEdges = inEdges.ToDictionary(edge => edge.EdgeAlias,
edge => new Tuple <MatchEdge, EdgeDir>(edge, EdgeDir.In));
extInEdges = inEdges.ToDictionary(edge => edge.EdgeAlias);
}
foreach (var edge in outEdges)
{
var key = edge.EdgeAlias;
rawEdges.Add(key, new Tuple <MatchEdge, EdgeDir>(edge, EdgeDir.Out));
extInEdges.Add(key, revEdgeDict[key]);
}
if (extInEdges.Any())
{
var firstEdge = extInEdges.FirstOrDefault(e => e.Value.IsReversed == false);
if (firstEdge.Value == null)
{
firstEdge = extInEdges.First();
}
var preMatInEdges = new Dictionary <string, MatchEdge>
{
{ firstEdge.Key, firstEdge.Value }
};
var postMatEdges = rawEdges.Where(entry => !preMatInEdges.ContainsKey(entry.Key))
.Select(entry => entry.Value).ToList();
// Both edge will be forced to choose the incoming direction type
var postMatIncomingEdges = postMatEdges.Where(entry => entry.Item2 == EdgeDir.In || (entry.Item2 == EdgeDir.Out && entry.Item1.EdgeType == WEdgeType.BothEdge))
.Select(entry => (entry.Item2 == EdgeDir.In ? entry.Item1 : revEdgeDict[entry.Item1.EdgeAlias])).ToList();
var postMatOutgoingEdges = postMatEdges.Where(entry => entry.Item2 == EdgeDir.Out && entry.Item1.EdgeType != WEdgeType.BothEdge)
.Select(entry => entry.Item1).ToList();
return(new CandidateJoinUnit
{
TreeRoot = root,
PreMatIncomingEdges = preMatInEdges.Select(entry => entry.Value).ToList(),
PreMatOutgoingEdges = new List <MatchEdge>(),
PostMatIncomingEdges = postMatIncomingEdges,
PostMatOutgoingEdges = postMatOutgoingEdges,
UnmaterializedEdges = unpopEdges,
});
}
else
{
throw new GraphViewException("This graph pattern is not yet supported.");
}
}
private CandidateJoinUnit GetCandidateUnits(OneHeightTree tree, MatchComponent component)
{
var nodeMatEdgesDict = component.NodeToMaterializedEdgesDict;
var revEdgeDict = Graph.ReversedEdgeDict;
var root = tree.TreeRoot;
nodeMatEdgesDict[root.NodeAlias] = new List <Tuple <MatchEdge, MaterializedEdgeType> >();
List <MatchEdge> inEdges;
component.UnmaterializedNodeMapping.TryGetValue(root, out inEdges);
var outEdges = new List <MatchEdge>();
var unpopEdges = new List <MatchEdge>();
foreach (var edge in tree.Edges)
{
if (component.Nodes.Contains(edge.SinkNode))
{
outEdges.Add(edge);
}
else
{
unpopEdges.Add(edge);
}
}
var rawEdges = new Dictionary <string, Tuple <MatchEdge, EdgeDir> >();
var extInEdges = new Dictionary <string, MatchEdge>();
if (inEdges != null)
{
rawEdges = inEdges.ToDictionary(edge => edge.EdgeAlias,
edge => new Tuple <MatchEdge, EdgeDir>(edge, EdgeDir.In));
extInEdges = inEdges.ToDictionary(edge => edge.EdgeAlias);
}
foreach (var edge in outEdges)
{
var key = edge.EdgeAlias;
rawEdges.Add(key, new Tuple <MatchEdge, EdgeDir>(edge, EdgeDir.Out));
extInEdges.Add(key, revEdgeDict[key]);
}
if (extInEdges.Any())
{
var firstEdge = extInEdges.FirstOrDefault(e => e.Value.IsReversed == false);
if (firstEdge.Value == null)
{
firstEdge = extInEdges.First();
}
var preMatInEdges = new Dictionary <string, MatchEdge>
{
{ firstEdge.Key, firstEdge.Value }
};
var postMatEdges = rawEdges.Where(entry => !preMatInEdges.ContainsKey(entry.Key))
.Select(entry => entry.Value).ToList();
var postMatIncomingEdges = postMatEdges.Where(entry => entry.Item2 == EdgeDir.In)
.Select(entry => entry.Item1).ToList();
var postMatOutgoingEdges = postMatEdges.Where(entry => entry.Item2 == EdgeDir.Out)
.Select(entry => entry.Item1).ToList();
nodeMatEdgesDict[firstEdge.Value.SourceNode.NodeAlias].Add(
new Tuple <MatchEdge, MaterializedEdgeType>(firstEdge.Value, MaterializedEdgeType.TraversalEdge));
foreach (var t in postMatEdges)
{
var edge = t.Item1;
var type = t.Item2 == EdgeDir.In
? MaterializedEdgeType.RemainingEdge
: MaterializedEdgeType.ReverseCheckEdge;
nodeMatEdgesDict[edge.SourceNode.NodeAlias].Add(new Tuple <MatchEdge, MaterializedEdgeType>(edge, type));
}
return(new CandidateJoinUnit
{
TreeRoot = root,
PreMatIncomingEdges = preMatInEdges.Select(entry => entry.Value).ToList(),
PreMatOutgoingEdges = new List <MatchEdge>(),
PostMatIncomingEdges = postMatIncomingEdges,
PostMatOutgoingEdges = postMatOutgoingEdges,
UnmaterializedEdges = unpopEdges,
});
}
else
{
throw new GraphViewException("This graph pattern is not yet supported.");
}
}
/// <summary>
/// Transit from current component to the new component in the next state given the Node Unit
/// </summary>
/// <param name="candidateTree"></param>
/// <param name="densityDict"></param>
/// <param name="subGraph"></param>
/// <param name="statisticsCalculator"></param>
/// <returns></returns>
public MatchComponent GetNextState(
OneHeightTree candidateTree,
Dictionary<string, double> densityDict,
IMatchJoinStatisticsCalculator statisticsCalculator)
{
var newComponent = new MatchComponent(this);
var root = candidateTree.TreeRoot;
WBooleanExpression joinCondition = null;
string nodeName = "";
// Update Nodes
if (newComponent.MaterializedNodeSplitCount.ContainsKey(root))
{
newComponent.MaterializedNodeSplitCount[root]++;
nodeName = newComponent.GetNodeRefName(root);
joinCondition = new WBooleanComparisonExpression
{
FirstExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {Value = root.RefAlias},
new Identifier {Value = "GlobalNodeId"}
),
},
SecondExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {Value = nodeName},
new Identifier {Value = "GlobalNodeId"}
),
},
ComparisonType = BooleanComparisonType.Equals
};
}
else
{
nodeName = root.RefAlias;
newComponent.Nodes.Add(root);
newComponent.MaterializedNodeSplitCount[root] = 0;
newComponent.StatisticsDict[root] = new ColumnStatistics {Selectivity = 1.0/root.TableRowCount};
}
// Constructs table reference
WTableReference nodeTable = new WNamedTableReference
{
Alias = new Identifier { Value = nodeName },
TableObjectName = root.TableObjectName
};
WTableReference compTable = newComponent.TableRef;
// Updates join conditions
double selectivity = 1.0;
double degrees = 1.0;
var DensityCount = new Dictionary<string, int>(StringComparer.CurrentCultureIgnoreCase);
List<MatchEdge> inEdges;
if (newComponent.UnmaterializedNodeMapping.TryGetValue(root, out inEdges))
{
var firstEdge = inEdges.First();
bool materialized = newComponent.EdgeMaterilizedDict[firstEdge];
newComponent.UnmaterializedNodeMapping.Remove(root);
selectivity *= 1.0/root.TableRowCount;
// Component materialized edge to root
if (materialized)
{
joinCondition = WBooleanBinaryExpression.Conjunction(joinCondition, new WBooleanComparisonExpression
{
FirstExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {Value = firstEdge.EdgeAlias},
new Identifier {Value = "Sink"}
),
},
SecondExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {Value = nodeName},
new Identifier {Value = "GlobalNodeId"}
)
},
ComparisonType = BooleanComparisonType.Equals
});
//var statistics = ColumnStatistics.UpdateHistogram(newComponent.StatisticsDict[root],
// new ColumnStatistics {Selectivity = 1.0/root.TableRowCount});
//selectivity *= statistics.Selectivity;
//newComponent.StatisticsDict[root] = statistics;
if (DensityCount.ContainsKey(root.TableObjectName.ToString()))
DensityCount[root.TableObjectName.ToString()]++;
else
DensityCount[root.TableObjectName.ToString()] = 1;
}
// Component unmaterialized edge to root
else
{
ColumnStatistics statistics = null;
foreach (var edge in inEdges)
{
// Update component table
compTable = SpanTableRef(compTable, edge, newComponent.GetNodeRefName(edge.SourceNode));
newComponent.EdgeMaterilizedDict[edge] = true;
joinCondition = WBooleanBinaryExpression.Conjunction(joinCondition,
new WBooleanComparisonExpression
{
FirstExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {Value = edge.EdgeAlias},
new Identifier {Value = "Sink"}
),
},
SecondExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {Value = nodeName},
new Identifier {Value = "GlobalNodeId"}
)
},
ComparisonType = BooleanComparisonType.Equals
});
statistics = ColumnStatistics.UpdateHistogram(statistics,
newComponent.Context.GetEdgeStatistics(edge));
selectivity *= statistics.Selectivity;
}
newComponent.StatisticsDict[root] = statistics;
if (DensityCount.ContainsKey(root.TableObjectName.ToString()))
DensityCount[root.TableObjectName.ToString()]+=inEdges.Count;
else
DensityCount[root.TableObjectName.ToString()] = inEdges.Count;
}
}
var jointEdges = candidateTree.MaterializedEdges;
int sinkToSinkCount = 0;
foreach (var jointEdge in jointEdges)
{
// Update node table
nodeTable = SpanTableRef(nodeTable, jointEdge, nodeName);
degrees *= jointEdge.AverageDegree;
newComponent.EdgeMaterilizedDict[jointEdge] = true;
var sinkNode = jointEdge.SinkNode;
// Leaf to component materialized node
if (newComponent.MaterializedNodeSplitCount.ContainsKey(sinkNode))
{
joinCondition = WBooleanBinaryExpression.Conjunction(joinCondition,
new WBooleanComparisonExpression
{
FirstExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {Value = jointEdge.EdgeAlias},
new Identifier {Value = "Sink"}
),
},
SecondExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {Value = sinkNode.RefAlias},
new Identifier {Value = "GlobalNodeId"}
)
},
ComparisonType = BooleanComparisonType.Equals
});
var statistics = ColumnStatistics.UpdateHistogram(newComponent.StatisticsDict[sinkNode],
newComponent.Context.GetEdgeStatistics(jointEdge));
selectivity *= statistics.Selectivity;
newComponent.StatisticsDict[sinkNode] = statistics;
if (DensityCount.ContainsKey(sinkNode.TableObjectName.ToString()))
DensityCount[sinkNode.TableObjectName.ToString()]++;
else
DensityCount[sinkNode.TableObjectName.ToString()] = 1;
}
// Leaf to component unmaterialized node
else
{
inEdges = newComponent.UnmaterializedNodeMapping[sinkNode];
var firstEdge = inEdges.First();
bool materlizedEdge = newComponent.EdgeMaterilizedDict[firstEdge];
// Leaf to materialized leaf
if (materlizedEdge)
{
joinCondition = WBooleanBinaryExpression.Conjunction(joinCondition,
new WBooleanComparisonExpression
{
FirstExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier {Value = jointEdge.EdgeAlias},
new Identifier {Value = "Sink"}
),
},
SecondExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier { Value = firstEdge.EdgeAlias},
new Identifier {Value = "Sink"}
)
},
ComparisonType = BooleanComparisonType.Equals
});
sinkToSinkCount++;
var statistics = ColumnStatistics.UpdateHistogram(newComponent.StatisticsDict[sinkNode],
newComponent.Context.GetEdgeStatistics(jointEdge));
selectivity *= statistics.Selectivity;
newComponent.StatisticsDict[sinkNode] = statistics;
}
// Leaf to unmaterialized leaf
else
{
ColumnStatistics compSinkNodeStatistics = null;
foreach (var inEdge in inEdges)
{
compTable = SpanTableRef(compTable, inEdge, newComponent.GetNodeRefName(inEdge.SourceNode));
newComponent.EdgeMaterilizedDict[inEdge] = true;
joinCondition = WBooleanBinaryExpression.Conjunction(joinCondition,
new WBooleanComparisonExpression
{
FirstExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier { Value = jointEdge.EdgeAlias },
new Identifier { Value = "Sink" }
),
},
SecondExpr = new WColumnReferenceExpression
{
ColumnType = ColumnType.Regular,
MultiPartIdentifier = new WMultiPartIdentifier(
new Identifier { Value = inEdge.EdgeAlias },
new Identifier { Value = "Sink" }
)
},
ComparisonType = BooleanComparisonType.Equals
});
sinkToSinkCount++;
var leafToLeafStatistics = statisticsCalculator.GetLeafToLeafStatistics(jointEdge, inEdge);
selectivity *= leafToLeafStatistics.Selectivity;
compSinkNodeStatistics =
ColumnStatistics.UpdateHistogram(compSinkNodeStatistics,
newComponent.Context.GetEdgeStatistics(inEdge));
}
newComponent.StatisticsDict[sinkNode] = compSinkNodeStatistics;
}
}
}
var unmatEdges = candidateTree.UnmaterializedEdges;
foreach (var unmatEdge in unmatEdges)
{
newComponent.EdgeMaterilizedDict[unmatEdge] = false;
newComponent.Nodes.Add(unmatEdge.SinkNode);
var sinkNodeInEdges = newComponent.UnmaterializedNodeMapping.GetOrCreate(unmatEdge.SinkNode);
sinkNodeInEdges.Add(unmatEdge);
degrees *= unmatEdge.AverageDegree;
}
// Calculate Estimated Join Selectivity & Estimated Node Size
double estimatedSelectity = 1.0;
int count = 0;
bool sinkJoin = false;
foreach (var item in densityDict.Where(e => DensityCount.ContainsKey(e.Key)))
{
var density = item.Value;
var curJoinCount = DensityCount[item.Key];
var curJoinSelectitivy = Math.Pow(density, 2 - Math.Pow(2, 1 - curJoinCount));
if (!sinkJoin && ColumnStatistics.DefaultDensity < density)
{
var curSinkJoinSelectivity = Math.Pow(ColumnStatistics.DefaultDensity,
2 - Math.Pow(2, 1 - sinkToSinkCount));
estimatedSelectity *= Math.Pow(curSinkJoinSelectivity, Math.Pow(2, -count));
count += sinkToSinkCount;
sinkJoin = true;
}
estimatedSelectity *= Math.Pow(curJoinSelectitivy, Math.Pow(2, -count));
count += curJoinCount;
}
var estimatedNodeUnitSize = root.EstimatedRows*
Math.Pow(1000, candidateTree.MaterializedEdges.Count + candidateTree.UnmaterializedEdges.Count);
// Update Table Reference
newComponent.TableRef = GetPlanAndUpdateCost(candidateTree, newComponent, nodeTable, compTable, joinCondition,
degrees, selectivity, estimatedNodeUnitSize, estimatedSelectity);
return newComponent;
}
/// <summary>
/// Calculate join costs and update components using optimal join method & order
/// </summary>
/// <param name="nodeUnitCandidate"></param>
/// <param name="component"></param>
/// <param name="nodeTable"></param>
/// <param name="componentTable"></param>
/// <param name="joinCondition"></param>
/// <param name="nodeDegrees"></param>
/// <param name="estimatedNodeUnitSize"></param>
/// <param name="estimatedSelectivity"></param>
/// <returns></returns>
private static WTableReference GetPlanAndUpdateCost(
OneHeightTree nodeUnitCandidate,
MatchComponent component,
WTableReference nodeTable,
WTableReference componentTable,
WBooleanExpression joinCondition,
double nodeDegrees,
double joinSelectivity,
double estimatedNodeUnitSize,
double estimatedSelectivity)
{
var nodeUnitSize = nodeUnitCandidate.TreeRoot.EstimatedRows * nodeDegrees;
var componentSize = component.Size;
var estimatedCompSize = component.EstimateSize;
var cost = nodeUnitSize + componentSize;
//var joinSelectivity =
// nodeWithJoinMapping.SelectivityProduct;
//nodeWithJoinMapping.ExponentialSelevtivityProduct;
WQualifiedJoin joinTable = new WQualifiedJoin
{
FirstTableRef = componentTable,
SecondTableRef = nodeTable,
JoinCondition = joinCondition,
QualifiedJoinType = QualifiedJoinType.Inner,
JoinHint = JoinHint.Hash
};
var node = nodeUnitCandidate.TreeRoot;
// If the node is already in the component, then only multiply the degree to get the size
double nodeUnitActualSize;
if (component.MaterializedNodeSplitCount[node] > 0)
{
nodeUnitActualSize = nodeDegrees;
var cEstEdge = Math.Pow(1000, component.EdgeMaterilizedDict.Count(e=>!e.Value));
var cSize = component.EstimateSize/cEstEdge;
var nSize = node.EstimatedRows;
if (nSize > cSize)
{
component.EstimateSize = estimatedNodeUnitSize*cEstEdge*estimatedSelectivity;
}
else
{
component.EstimateSize = component.EstimateSize*Math.Pow(1000, nodeUnitCandidate.UnmaterializedEdges.Count)*
estimatedSelectivity;
}
}
else
{
nodeUnitActualSize = nodeUnitSize;
component.EstimateSize *= estimatedNodeUnitSize * estimatedSelectivity;
}
//Update Size
component.Size *= nodeUnitActualSize * joinSelectivity;
// Update Cost
component.Cost += cost;
// Debug
#if DEBUG
//Trace.Write(component.NodeUnits.Count+" ");
//foreach (var n in component.NodeUnits.Where(e => e.Key != node.Node.ExposedName))
//{
// Trace.Write(n.Value.NodeRefName);
//}
//Trace.Write(component.NodeUnits[node.Node.ExposedName].NodeRefName+" ");
//Trace.Write(" "+(long)component.Cost+" "+(long)component.Size);
//Trace.Write(" ");
//foreach (var item in component.PopulatedEdgesName)
//{
// Trace.Write(item + " ");
//}
//Trace.Write("; ");
//foreach (var unpopulatedEdge in component.UnpopulatedEdges)
//{
// Trace.Write(unpopulatedEdge.Alias + " ");
//}
//Trace.WriteLine("");
#endif
// Update TableRef
// Only consider the size in the first join
if (component.MaterializedNodeSplitCount.Count == 2 && component.MaterializedNodeSplitCount.All(e => e.Value == 0))
{
var nodeInComp = component.MaterializedNodeSplitCount.Keys.First(e => e != node);
if (nodeUnitSize < componentSize)
{
joinTable.FirstTableRef = nodeTable;
joinTable.SecondTableRef = componentTable;
component.TotalMemory = component.DeltaMemory = nodeUnitSize;
component.EstimateTotalMemory = component.EstimateDeltaMemory = estimatedNodeUnitSize;
component.RightestTableRefSize = nodeInComp.EstimatedRows;
component.FatherOfRightestTableRef = new Tuple<WQualifiedJoin, String>(joinTable,
component.GetNodeRefName(nodeInComp));
AdjustEstimation(component, nodeTable, joinTable, nodeUnitSize, estimatedNodeUnitSize,
nodeUnitCandidate.TreeRoot.EstimatedRows, new Tuple<WQualifiedJoin, string>(joinTable, component.GetNodeRefName(node)));
}
else
{
component.TotalMemory = component.DeltaMemory = componentSize;
component.EstimateTotalMemory = component.EstimateDeltaMemory = component.EstimateSize;
component.RightestTableRefSize = nodeUnitCandidate.TreeRoot.EstimatedRows;
component.FatherOfRightestTableRef = new Tuple<WQualifiedJoin, String>(joinTable, component.GetNodeRefName(node));
AdjustEstimation(component, componentTable, joinTable, componentSize, estimatedCompSize,
nodeInComp.EstimatedRows, new Tuple<WQualifiedJoin, string>(joinTable, component.GetNodeRefName(nodeInComp)));
}
}
else
{
double sizeFactor = 5;//1000;
double maxMemory = 1e8;
double loopJoinInnerThreshold = 10000;
double loopJoinOuterThreshold = 1000000;
// Left Deep
if (componentSize*sizeFactor < nodeUnitSize)
{
var curDeltaMemory = componentSize;
component.TotalMemory = component.DeltaMemory + curDeltaMemory;
component.DeltaMemory = curDeltaMemory;
var curDeltaEstimateMemory = component.EstimateSize;
component.EstimateTotalMemory = component.EstimateDeltaMemory + curDeltaEstimateMemory;
component.EstimateDeltaMemory = curDeltaEstimateMemory;
// Adjust estimation in sql server
AdjustEstimation(component, componentTable, joinTable, componentSize, estimatedCompSize,
component.RightestTableRefSize, component.FatherOfRightestTableRef);
component.FatherOfRightestTableRef = new Tuple<WQualifiedJoin, string>(joinTable, component.GetNodeRefName(node));
component.RightestTableRefSize = nodeUnitCandidate.TreeRoot.EstimatedRows;
}
else
{
// Loop Join
if (
//((nodeUnitSize < loopJoinInnerThreshold /*&& componentSize < loopJoinOuterThreshold*/) || component.DeltaMemory + componentSize > maxMemory / 100) &&
((nodeUnitSize < loopJoinInnerThreshold && componentSize < loopJoinOuterThreshold) ||
component.DeltaMemory + componentSize > maxMemory) &&
nodeUnitCandidate.MaterializedEdges.Count==0)
{
component.TotalMemory = component.DeltaMemory;
component.EstimateTotalMemory = component.EstimateDeltaMemory;
joinTable.JoinHint = JoinHint.Loop;
component.EstimateSize = estimatedCompSize*estimatedNodeUnitSize/
nodeUnitCandidate.TreeRoot.TableRowCount;
}
// Right Deep
else
{
joinTable.FirstTableRef = nodeTable;
joinTable.SecondTableRef = componentTable;
AdjustEstimation(component, nodeTable, joinTable, nodeUnitSize, estimatedNodeUnitSize,
node.EstimatedRows, new Tuple<WQualifiedJoin, string>(joinTable, component.GetNodeRefName(node)));
component.TotalMemory += nodeUnitSize;
component.DeltaMemory = component.TotalMemory;
component.EstimateTotalMemory += estimatedNodeUnitSize;
component.EstimateDeltaMemory = component.EstimateTotalMemory;
}
}
}
return new WParenthesisTableReference
{
Table = joinTable
};
}
private CandidateJoinUnit GetCandidateUnits2(OneHeightTree tree, MatchComponent component)
{
Dictionary <string, MatchEdge> revEdgeDict = this.Graph.ReversedEdgeDict;
MatchNode root = tree.TreeRoot;
List <MatchEdge> inEdges;
component.UnmaterializedNodeMapping.TryGetValue(root, out inEdges);
List <MatchEdge> outEdges = new List <MatchEdge>();
List <MatchEdge> unpopEdges = new List <MatchEdge>();
foreach (MatchEdge edge in tree.Edges)
{
if (component.Nodes.ContainsKey(edge.SinkNode.NodeAlias))
{
outEdges.Add(edge);
}
else
{
unpopEdges.Add(edge);
}
}
Dictionary <string, Tuple <MatchEdge, EdgeDir> > rawEdges = new Dictionary <string, Tuple <MatchEdge, EdgeDir> >();
Dictionary <string, MatchEdge> extInEdges = new Dictionary <string, MatchEdge>();
if (inEdges != null)
{
rawEdges = inEdges.ToDictionary(edge => edge.EdgeAlias,
edge => new Tuple <MatchEdge, EdgeDir>(edge, EdgeDir.In));
extInEdges = inEdges.ToDictionary(edge => edge.EdgeAlias);
}
foreach (MatchEdge edge in outEdges)
{
string key = edge.EdgeAlias;
rawEdges.Add(key, new Tuple <MatchEdge, EdgeDir>(edge, EdgeDir.Out));
extInEdges.Add(key, revEdgeDict[key]);
}
if (extInEdges.Any())
{
KeyValuePair <string, MatchEdge> firstEdge = extInEdges.FirstOrDefault(e => e.Value.IsReversed == false);
if (firstEdge.Value == null)
{
firstEdge = extInEdges.First();
}
Dictionary <string, MatchEdge> preMatInEdges = new Dictionary <string, MatchEdge>
{
{ firstEdge.Key, firstEdge.Value }
};
List <Tuple <MatchEdge, EdgeDir> > postMatEdges = rawEdges.Where(entry => !preMatInEdges.ContainsKey(entry.Key))
.Select(entry => entry.Value).ToList();
List <MatchEdge> postMatIncomingEdges =
postMatEdges.Where(entry => entry.Item2 == EdgeDir.In).Select(entry => entry.Item1).ToList();
List <MatchEdge> postMatOutgoingEdges =
postMatEdges.Where(entry => entry.Item2 == EdgeDir.Out).Select(entry => entry.Item1).ToList();
return(new CandidateJoinUnit
{
TreeRoot = root,
PreMatIncomingEdges = preMatInEdges.Select(entry => entry.Value).ToList(),
PreMatOutgoingEdges = new List <MatchEdge>(),
PostMatIncomingEdges = postMatIncomingEdges,
PostMatOutgoingEdges = postMatOutgoingEdges,
UnmaterializedEdges = unpopEdges,
});
}
else
{
throw new GraphViewException("This graph pattern is not yet supported.");
}
}
