// <summary>
// Callback function to invoke *before* rules are applied.
// Calls the VarRemapper to update any Vars in the entire subtree
// If the given node has a RelOp it is pushed on the relOp ancestors stack.
// </summary>
internal override void PreProcessSubTree(Node subTree)
{
if (subTree.Op.IsRelOp)
{
m_relOpAncestors.Push(subTree);
}
if (m_remappedVars.IsEmpty)
{
return;
}
var nodeInfo = Command.GetNodeInfo(subTree);
//We need to do remapping only if m_remappedVars overlaps with nodeInfo.ExternalReferences
foreach (var v in nodeInfo.ExternalReferences)
{
if (m_remappedVars.IsSet(v))
{
m_remapper.RemapSubtree(subTree);
break;
}
}
}
private void TryProcessCandidate(
KeyValuePair<Node, Node> candidate,
GroupAggregateVarInfo groupAggregateVarInfo)
{
IList<Node> functionAncestors;
IList<Node> groupByAncestors;
var definingGroupNode = groupAggregateVarInfo.DefiningGroupNode;
FindPathsToLeastCommonAncestor(candidate.Key, definingGroupNode, out functionAncestors, out groupByAncestors);
//Check whether all ancestors of the GroupByInto node are of type that we support propagating through
if (!AreAllNodesSupportedForPropagation(groupByAncestors))
{
return;
}
//Add the function to the group by node
var definingGroupOp = (GroupByIntoOp)definingGroupNode.Op;
PlanCompiler.Assert(definingGroupOp.Inputs.Count == 1, "There should be one input var to GroupByInto at this stage");
var inputVar = definingGroupOp.Inputs.First;
var functionOp = (FunctionOp)candidate.Key.Op;
//
// Remap the template from referencing the groupAggregate var to reference the input to
// the group by into
//
var argumentNode = OpCopier.Copy(m_command, candidate.Value);
var dictionary = new Dictionary<Var, Var>(1);
dictionary.Add(groupAggregateVarInfo.GroupAggregateVar, inputVar);
var remapper = new VarRemapper(m_command, dictionary);
remapper.RemapSubtree(argumentNode);
var newFunctionDefiningNode = m_command.CreateNode(
m_command.CreateAggregateOp(functionOp.Function, false),
argumentNode);
Var newFunctionVar;
var varDefNode = m_command.CreateVarDefNode(newFunctionDefiningNode, out newFunctionVar);
// Add the new aggregate to the list of aggregates
definingGroupNode.Child2.Children.Add(varDefNode);
var groupByOp = (GroupByIntoOp)definingGroupNode.Op;
groupByOp.Outputs.Set(newFunctionVar);
//Propagate the new var throught the ancestors of the GroupByInto
for (var i = 0; i < groupByAncestors.Count; i++)
{
var groupByAncestor = groupByAncestors[i];
if (groupByAncestor.Op.OpType
== OpType.Project)
{
var ancestorProjectOp = (ProjectOp)groupByAncestor.Op;
ancestorProjectOp.Outputs.Set(newFunctionVar);
}
}
//Update the functionNode
candidate.Key.Op = m_command.CreateVarRefOp(newFunctionVar);
candidate.Key.Children.Clear();
}
// <summary>
// Convert a SingleStreamNestOp into a massive UnionAllOp
// </summary>
private Node BuildUnionAllSubqueryForNestOp(
NestBaseOp nestOp, Node nestNode, VarList drivingNodeVars, VarList discriminatorVarList, out Var discriminatorVar,
out List<Dictionary<Var, Var>> varMapList)
{
var drivingNode = nestNode.Child0;
// For each of the NESTED collections...
Node unionAllNode = null;
VarList unionAllOutputs = null;
for (var i = 1; i < nestNode.Children.Count; i++)
{
// Ensure we only use the driving collection tree once, so other
// transformations do not unintentionally change more than one path.
// To prevent nodes in the tree from being used in multiple paths,
// we copy the driving input on successive nodes.
VarList newDrivingNodeVars;
Node newDrivingNode;
VarList newFlattenedElementVars;
Op op;
if (i > 1)
{
newDrivingNode = OpCopier.Copy(Command, drivingNode, drivingNodeVars, out newDrivingNodeVars);
//
// Bug 450245: If we copied the driver node, then references to driver node vars
// from the collection subquery must be patched up
//
var varRemapper = new VarRemapper(Command);
for (var j = 0; j < drivingNodeVars.Count; j++)
{
varRemapper.AddMapping(drivingNodeVars[j], newDrivingNodeVars[j]);
}
// Remap all references in the current subquery
varRemapper.RemapSubtree(nestNode.Children[i]);
// Bug 479183: Remap the flattened element vars
newFlattenedElementVars = varRemapper.RemapVarList(nestOp.CollectionInfo[i - 1].FlattenedElementVars);
// Create a cross apply for all but the first collection
op = Command.CreateCrossApplyOp();
}
else
{
newDrivingNode = drivingNode;
newDrivingNodeVars = drivingNodeVars;
newFlattenedElementVars = nestOp.CollectionInfo[i - 1].FlattenedElementVars;
// Create an outer apply for the first collection,
// that way we ensure at least one row for each row in the driver node.
op = Command.CreateOuterApplyOp();
}
// Create an outer apply with the driver node and the nested collection.
var applyNode = Command.CreateNode(op, newDrivingNode, nestNode.Children[i]);
// Now create a ProjectOp that augments the output from the OuterApplyOp
// with nulls for each column from other collections
// Build the VarDefList (the list of vars) for the Project, starting
// with the collection discriminator var
var varDefListChildren = new List<Node>();
var projectOutputs = Command.CreateVarList();
// Add the collection discriminator var to the output.
projectOutputs.Add(discriminatorVarList[i]);
// Add all columns from the driving node
projectOutputs.AddRange(newDrivingNodeVars);
// Add all the vars from all the nested collections;
for (var j = 1; j < nestNode.Children.Count; j++)
{
var otherCollectionInfo = nestOp.CollectionInfo[j - 1];
// For the current nested collection, we just pick the var that's
// coming from there and don't need have a new var defined, but for
// the rest we construct null values.
if (i == j)
{
projectOutputs.AddRange(newFlattenedElementVars);
}
else
{
foreach (var v in otherCollectionInfo.FlattenedElementVars)
{
var nullOp = Command.CreateNullOp(v.Type);
var nullOpNode = Command.CreateNode(nullOp);
Var nullOpVar;
var nullOpVarDefNode = Command.CreateVarDefNode(nullOpNode, out nullOpVar);
varDefListChildren.Add(nullOpVarDefNode);
projectOutputs.Add(nullOpVar);
}
}
}
var varDefListNode = Command.CreateNode(Command.CreateVarDefListOp(), varDefListChildren);
// Now, build up the projectOp
var projectOutputsVarSet = Command.CreateVarVec(projectOutputs);
var projectOp = Command.CreateProjectOp(projectOutputsVarSet);
var projectNode = Command.CreateNode(projectOp, applyNode, varDefListNode);
// finally, build the union all
if (unionAllNode == null)
{
unionAllNode = projectNode;
unionAllOutputs = projectOutputs;
}
else
{
var unionAllMap = new VarMap();
var projectMap = new VarMap();
for (var idx = 0; idx < unionAllOutputs.Count; idx++)
{
Var outputVar = Command.CreateSetOpVar(unionAllOutputs[idx].Type);
unionAllMap.Add(outputVar, unionAllOutputs[idx]);
projectMap.Add(outputVar, projectOutputs[idx]);
}
var unionAllOp = Command.CreateUnionAllOp(unionAllMap, projectMap);
unionAllNode = Command.CreateNode(unionAllOp, unionAllNode, projectNode);
// Get the output vars from the union-op. This must be in the same order
// as the original list of Vars
unionAllOutputs = GetUnionOutputs(unionAllOp, unionAllOutputs);
}
}
// We're done building the node, but now we have to build a mapping from
// the before-Vars to the after-Vars
varMapList = new List<Dictionary<Var, Var>>();
IEnumerator<Var> outputVarsEnumerator = unionAllOutputs.GetEnumerator();
if (!outputVarsEnumerator.MoveNext())
{
throw EntityUtil.InternalError(EntityUtil.InternalErrorCode.ColumnCountMismatch, 4, null);
// more columns from children than are on the unionAll?
}
// The discriminator var is always first
discriminatorVar = outputVarsEnumerator.Current;
// Build a map for each input
for (var i = 0; i < nestNode.Children.Count; i++)
{
var varMap = new Dictionary<Var, Var>();
var varList = (i == 0) ? drivingNodeVars : nestOp.CollectionInfo[i - 1].FlattenedElementVars;
foreach (var v in varList)
{
if (!outputVarsEnumerator.MoveNext())
{
throw EntityUtil.InternalError(EntityUtil.InternalErrorCode.ColumnCountMismatch, 5, null);
// more columns from children than are on the unionAll?
}
varMap[v] = outputVarsEnumerator.Current;
}
varMapList.Add(varMap);
}
if (outputVarsEnumerator.MoveNext())
{
throw EntityUtil.InternalError(EntityUtil.InternalErrorCode.ColumnCountMismatch, 6, null);
// at this point, we better be done with both lists...
}
return unionAllNode;
}
private void TryProcessCandidate(
KeyValuePair <Node, Node> candidate,
GroupAggregateVarInfo groupAggregateVarInfo)
{
IList <Node> functionAncestors;
IList <Node> groupByAncestors;
var definingGroupNode = groupAggregateVarInfo.DefiningGroupNode;
FindPathsToLeastCommonAncestor(candidate.Key, definingGroupNode, out functionAncestors, out groupByAncestors);
//Check whether all ancestors of the GroupByInto node are of type that we support propagating through
if (!AreAllNodesSupportedForPropagation(groupByAncestors))
{
return;
}
//Add the function to the group by node
var definingGroupOp = (GroupByIntoOp)definingGroupNode.Op;
PlanCompiler.Assert(definingGroupOp.Inputs.Count == 1, "There should be one input var to GroupByInto at this stage");
var inputVar = definingGroupOp.Inputs.First;
var functionOp = (FunctionOp)candidate.Key.Op;
//
// Remap the template from referencing the groupAggregate var to reference the input to
// the group by into
//
var argumentNode = OpCopier.Copy(m_command, candidate.Value);
var dictionary = new Dictionary <Var, Var>(1);
dictionary.Add(groupAggregateVarInfo.GroupAggregateVar, inputVar);
var remapper = new VarRemapper(m_command, dictionary);
remapper.RemapSubtree(argumentNode);
var newFunctionDefiningNode = m_command.CreateNode(
m_command.CreateAggregateOp(functionOp.Function, false),
argumentNode);
Var newFunctionVar;
var varDefNode = m_command.CreateVarDefNode(newFunctionDefiningNode, out newFunctionVar);
// Add the new aggregate to the list of aggregates
definingGroupNode.Child2.Children.Add(varDefNode);
var groupByOp = (GroupByIntoOp)definingGroupNode.Op;
groupByOp.Outputs.Set(newFunctionVar);
//Propagate the new var throught the ancestors of the GroupByInto
for (var i = 0; i < groupByAncestors.Count; i++)
{
var groupByAncestor = groupByAncestors[i];
if (groupByAncestor.Op.OpType
== OpType.Project)
{
var ancestorProjectOp = (ProjectOp)groupByAncestor.Op;
ancestorProjectOp.Outputs.Set(newFunctionVar);
}
}
//Update the functionNode
candidate.Key.Op = m_command.CreateVarRefOp(newFunctionVar);
candidate.Key.Children.Clear();
}