private static ResultAlgebraNode Convert(CommonTableBinding currentCommonTableBinding, QueryNode queryNode)
{
Algebrizer algebrizer = new Algebrizer(currentCommonTableBinding);
AlgebraNode result = algebrizer.ConvertAstNode(queryNode);
result = new SubqueryExpander().VisitAlgebraNode(result);
return (ResultAlgebraNode)result;
}
private static ResultAlgebraNode Convert(CommonTableBinding currentCommonTableBinding, QueryNode queryNode)
{
Algebrizer algebrizer = new Algebrizer(currentCommonTableBinding);
AlgebraNode result = algebrizer.ConvertAstNode(queryNode);
result = new SubqueryExpander().VisitAlgebraNode(result);
return((ResultAlgebraNode)result);
}
public ResultAlgebraNode CompileQuery(string queryText, Scope scope)
{
// Algebraization
Parser parser = new Parser(_errorReporter);
QueryNode parsedQuery = parser.ParseQuery(queryText);
// When the parser detected errors or could not even construct an AST it
// does not make any sense to go ahead.
if (_errorReporter.ErrorsSeen || parsedQuery == null)
{
return(null);
}
PhaseRunner phaseRunner = new PhaseRunner(_errorReporter, parsedQuery);
phaseRunner.Phases.Add(PHASE_NORMALIZATION, new Normalizer());
phaseRunner.Phases.Add(PHASE_RESOLUTION, new Resolver(_errorReporter, scope));
phaseRunner.Phases.Add(PHASE_AGGREGATE_BINDING, new AggregateBinder(_errorReporter));
phaseRunner.Phases.Add(PHASE_VALIDATION, new Validator(_errorReporter, scope.DataContext.MetadataContext));
phaseRunner.Phases.Add(PHASE_CONSTANT_FOLDING, new ConstantFolder(_errorReporter));
phaseRunner.Phases.Add(PHASE_COLUMN_AND_AGGREGATE_EXPRESSION_REPLACEMENT, new ColumnAndAggregateExpressionReplacer());
phaseRunner.Phases.Add(PHASE_ALGEBRAIZATION, delegate(AstNode input)
{
return(Algebrizer.Convert((QueryNode)input));
});
phaseRunner.Phases.Add(PHASE_ROW_BUFFER_ENTRY_INLINING, new RowBufferEntryInliner());
phaseRunner.Phases.Add(PHASE_SEMI_JOIN_SIMPLIFICATION, new SemiJoinSimplifier());
phaseRunner.Phases.Add(PHASE_DECORRELATION, new Decorrelator());
phaseRunner.Phases.Add(PHASE_OUTER_JOIN_REMOVAL, new OuterJoinRemover());
phaseRunner.Phases.Add(PHASE_SELECTION_PUSHING, new SelectionPusher());
phaseRunner.Phases.Add(PHASE_JOIN_LINEARIZATION, new JoinLinearizer());
phaseRunner.Phases.Add(PHASE_OUTER_JOIN_REORDERING, new OuterJoinReorderer());
phaseRunner.Phases.Add(PHASE_JOIN_ORDER_OPTIMIZATION, new JoinOrderOptimizer());
phaseRunner.Phases.Add(PHASE_AT_MOST_ONE_ROW_REORDERING, new AtMostOneRowReorderer());
phaseRunner.Phases.Add(PHASE_OUTER_REFERENCE_LABELING, new OuterReferenceLabeler());
phaseRunner.Phases.Add(PHASE_SPOOL_INSERTION, new SpoolInserter());
phaseRunner.Phases.Add(PHASE_PUSH_COMPUTATIONS, new ComputationPusher());
phaseRunner.Phases.Add(PHASE_PHYSICAL_JOIN_OP_CHOOSING, new PhysicalJoinOperationChooser());
phaseRunner.Phases.Add(PHASE_OUTPUTLIST_GENERATION, new OutputListGenerator());
phaseRunner.Phases.Add(PHASE_NULL_SCAN_OPTIMIZATION, new NullScanOptimizer());
phaseRunner.Phases.Add(PHASE_FULL_OUTER_JOIN_EXPANSION, new FullOuterJoinExpander());
phaseRunner.Phases.Add(PHASE_OUTPUTLIST_OPTIMIZATION, new OutputListOptimizer());
phaseRunner.Phases.Add(PHASE_ROW_BUFFER_ENTRY_NAMING, new RowBufferEntryNamer());
// TODO: Acutally, we should perform "PushComputations" after "NullScanOptimization" since
// we can merge some ComputeScalar nodes there. But currently the "PushComputations"
// visitor does not correctly update the OutputList so later phases will fail.
// TODO: The phases "SpoolInsertion" and "PhysicalJoinOperationChoosing" should be the last
// entries but currently they must precede PHASE_OUTPUTLIST_GENERATION, PHASE_OUTPUTLIST_OPTIMIZATION,
// and PHASE_ROW_BUFFER_ENTRY_NAMING.
return((ResultAlgebraNode)phaseRunner.Run());
}
public override ExpressionNode VisitSingleRowSubselect(SingleRowSubselect expression)
{
AlgebraNode inputNode = GetOrCreateInput();
ResultAlgebraNode algebrizedSubquery = Algebrizer.Convert(expression.Query);
ResultAlgebraNode assertedSubquery = CreateAssertedSubquery(algebrizedSubquery);
JoinAlgebraNode joinAlgebraNode = new JoinAlgebraNode();
joinAlgebraNode.PassthruPredicate = CurrentPassthruPredicate;
joinAlgebraNode.Op = JoinAlgebraNode.JoinOperator.LeftOuterJoin;
joinAlgebraNode.Left = inputNode;
joinAlgebraNode.Right = assertedSubquery;
SetLastAlgebraNode(joinAlgebraNode);
return(new RowBufferEntryExpression(assertedSubquery.OutputList[0]));
}
public override ExpressionNode VisitExistsSubselect(ExistsSubselect expression)
{
AlgebraNode input = GetAndResetLastNode();
ResultAlgebraNode algebrizedQuery = Algebrizer.Convert(expression.Query);
if (!expression.Negated && AstUtil.WillProduceAtLeastOneRow(algebrizedQuery))
{
if (input == null)
{
SetLastAlgebraNode(CreateConstantScan());
}
else
{
SetLastAlgebraNode(input);
}
return(LiteralExpression.FromBoolean(true));
}
if (!expression.Negated && !ProbingEnabled && input == null)
{
SetLastAlgebraNode(algebrizedQuery);
return(LiteralExpression.FromBoolean(true));
}
else
{
if (input == null)
{
input = CreateConstantScan();
}
RowBufferEntry probeColumn = CreateProbeColumn();
JoinAlgebraNode joinAlgebraNode = new JoinAlgebraNode();
joinAlgebraNode.PassthruPredicate = CurrentPassthruPredicate;
joinAlgebraNode.ProbeBufferEntry = probeColumn;
joinAlgebraNode.Left = input;
joinAlgebraNode.Right = algebrizedQuery;
joinAlgebraNode.Op = expression.Negated ? JoinAlgebraNode.JoinOperator.LeftAntiSemiJoin : JoinAlgebraNode.JoinOperator.LeftSemiJoin;
SetLastAlgebraNode(joinAlgebraNode);
return(CreateProbeColumnRef(probeColumn));
}
}
public override ExpressionNode VisitAllAnySubselect(AllAnySubselect expression)
{
expression.Left = VisitExpression(expression.Left);
ResultAlgebraNode algebrizedQuery = Algebrizer.Convert(expression.Query);
ExpressionNode leftExpression = expression.Left;
RowBufferEntryExpression rightExpression = new RowBufferEntryExpression();
rightExpression.RowBufferEntry = algebrizedQuery.OutputList[0];
ExpressionBuilder expressionBuilder = new ExpressionBuilder();
expressionBuilder.Push(leftExpression);
expressionBuilder.Push(rightExpression);
expressionBuilder.PushBinary(expression.Op);
bool negated = (expression.Type == AllAnySubselect.AllAnyType.All);
if (negated)
{
expressionBuilder.PushUnary(UnaryOperator.LogicalNot);
expressionBuilder.Push(leftExpression);
expressionBuilder.PushIsNull();
expressionBuilder.Push(rightExpression);
expressionBuilder.PushIsNull();
expressionBuilder.PushNAry(LogicalOperator.Or);
}
ExpressionNode filterPredicate = expressionBuilder.Pop();
FilterAlgebraNode filterAlgebraNode = new FilterAlgebraNode();
filterAlgebraNode.Input = algebrizedQuery;
filterAlgebraNode.Predicate = filterPredicate;
AlgebraNode input = GetAndResetLastNode();
if (!negated && !ProbingEnabled && input == null)
{
SetLastAlgebraNode(filterAlgebraNode);
return(LiteralExpression.FromBoolean(true));
}
else
{
if (input == null)
{
input = CreateConstantScan();
}
RowBufferEntry probeColumn = CreateProbeColumn();
JoinAlgebraNode joinAlgebraNode = new JoinAlgebraNode();
joinAlgebraNode.PassthruPredicate = CurrentPassthruPredicate;
joinAlgebraNode.ProbeBufferEntry = probeColumn;
joinAlgebraNode.Left = input;
joinAlgebraNode.Right = filterAlgebraNode;
joinAlgebraNode.Op = negated ? JoinAlgebraNode.JoinOperator.LeftAntiSemiJoin : JoinAlgebraNode.JoinOperator.LeftSemiJoin;
SetLastAlgebraNode(joinAlgebraNode);
return(CreateProbeColumnRef(probeColumn));
}
}