public FilterExprAnalyzerAffector GetFilterExprAnalyzerAffector()
{
var visitor = new ExprNodeIdentifierAndStreamRefVisitor(false);
foreach (ExprNode lhsNode in _lhs)
{
lhsNode.Accept(visitor);
}
var indexedPropertyStreams = new HashSet <int>();
foreach (ExprNodePropOrStreamDesc @ref in visitor.GetRefs())
{
indexedPropertyStreams.Add(@ref.StreamNum);
}
if (indexedPropertyStreams.Count == 0 || indexedPropertyStreams.Count > 1)
{
return
(null); // there are no properties from any streams that could be used for building an index, or the properties come from different disjoint streams
}
var streamNumIndex = indexedPropertyStreams.First();
var keyExpressions = new List <Pair <ExprNode, int[]> >();
var dependencies = new HashSet <int>();
foreach (ExprNode node in _rhs)
{
visitor.Reset();
dependencies.Clear();
node.Accept(visitor);
foreach (ExprNodePropOrStreamDesc @ref in visitor.GetRefs())
{
dependencies.Add(@ref.StreamNum);
}
if (dependencies.Contains(streamNumIndex))
{
return(null);
}
var pair = new Pair <ExprNode, int[]>(node, CollectionUtil.IntArray(dependencies));
keyExpressions.Add(pair);
}
return(new FilterExprAnalyzerAffectorIndexProvision(OperationName, _lhs, keyExpressions, streamNumIndex));
}
private static EventAdvancedIndexProvisionDesc ValidateAdvanced(
string indexName,
string indexType,
CreateIndexItem columnDesc,
EventType eventType,
StatementContext statementContext)
{
// validate index expressions: valid and plain expressions
ExprValidationContext validationContextColumns = GetValidationContext(eventType, statementContext);
ExprNode[] columns = columnDesc.Expressions.ToArray();
ExprNodeUtility.GetValidatedSubtree(ExprNodeOrigin.CREATEINDEXCOLUMN, columns, validationContextColumns);
ExprNodeUtility.ValidatePlainExpression(ExprNodeOrigin.CREATEINDEXCOLUMN, columns);
// validate parameters, may not depend on props
ExprNode[] parameters = null;
if (columnDesc.Parameters != null && !columnDesc.Parameters.IsEmpty())
{
parameters = columnDesc.Parameters.ToArray();
ExprNodeUtility.GetValidatedSubtree(ExprNodeOrigin.CREATEINDEXPARAMETER, parameters, validationContextColumns);
ExprNodeUtility.ValidatePlainExpression(ExprNodeOrigin.CREATEINDEXPARAMETER, parameters);
// validate no stream dependency of parameters
var visitor = new ExprNodeIdentifierAndStreamRefVisitor(false);
foreach (ExprNode param in columnDesc.Parameters)
{
param.Accept(visitor);
if (!visitor.GetRefs().IsEmpty())
{
throw new ExprValidationException("Index parameters may not refer to event properties");
}
}
}
// obtain provider
AdvancedIndexFactoryProvider provider;
try {
provider = statementContext.EngineImportService.ResolveAdvancedIndexProvider(indexType);
} catch (EngineImportException ex) {
throw new ExprValidationException(ex.Message, ex);
}
return(provider.ValidateEventIndex(indexName, indexType, columns, parameters));
}