public static void ValidateLateArrivingLookup(AstLateArrivingLookupNode lookup)
{
if (!lookup.Table.LateArriving)
{
MessageEngine.Trace(lookup, Severity.Error, "V0128", "Table {0} is not designated for Late Arriving Lookup. Set LateArriving = true.", lookup.Table.Name);
}
AstTableKeyBaseNode eligibleKey = null;
foreach (AstTableKeyBaseNode key in lookup.Table.Keys)
{
if (key.Columns.Any(keyColumn => !keyColumn.Column.IsComputed))
{
eligibleKey = key;
break; // Safe to do since we already verified single eligble key in the table processing pass
}
}
if (eligibleKey == null)
{
MessageEngine.Trace(lookup, Severity.Error, "V0129", "Late Arriving Table {0} must specify an eligible key.", lookup.Table.Name);
}
// TODO: Finish checking this logic
foreach (AstTableKeyColumnNode eligibleKeyColumn in eligibleKey.Columns)
{
if (!lookup.Inputs.Any(io => io.RemoteColumnName == eligibleKeyColumn.Column.Name))
{
MessageEngine.Trace(lookup, Severity.Error, "V0123", "Late Arriving Lookup {0} must specify inputs for every column of constraint: {1}", lookup.Name, eligibleKey.Name);
}
}
}
private static AstOleDBCommandNode CreateInsertNode(AstLateArrivingLookupNode lookup, AstLookupNode codegenLookup)
{
var insertPlaceholder = new AstOleDBCommandNode(lookup.ParentItem)
{
Name = String.Format(CultureInfo.InvariantCulture, "__LALookupPlaceholderInsert_{0}", lookup.Name),
Connection = lookup.Table.Connection,
};
insertPlaceholder.Query = new AstTransformationMappedQueryNode(insertPlaceholder) { Body = TableLowerer.EmitInsertDefaultRowStatement(lookup.Table) };
insertPlaceholder.InputPath = new AstDataflowMappedInputPathNode(insertPlaceholder) { OutputPath = codegenLookup.NoMatchPath };
return insertPlaceholder;
}
private static void ProcessLateArrivingLookup(AstLateArrivingLookupNode lookup)
{
AstLowererValidation.ValidateLateArrivingLookup(lookup);
var workflowFragment = new List<AstTransformationNode>();
AstLookupNode codegenLookup = CreateLookupNode(lookup);
AstOleDBCommandNode insertPlaceholder = CreateInsertNode(lookup, codegenLookup);
AstUnionAllNode unionAll = CreateUnionAllNode(lookup, codegenLookup, insertPlaceholder);
workflowFragment.Add(codegenLookup);
workflowFragment.Add(insertPlaceholder);
workflowFragment.Add(unionAll);
Utility.Replace(lookup, workflowFragment);
}
private static AstUnionAllNode CreateUnionAllNode(AstLateArrivingLookupNode lookup, AstLookupNode codegenLookup, AstOleDBCommandNode insertPlaceholder)
{
var unionAll = new AstUnionAllNode(lookup.ParentItem) { Name = String.Format(CultureInfo.InvariantCulture, "__LALookupUnionAll_{0}", lookup.Name) };
unionAll.InputPaths.Add(new AstDataflowMappedInputPathNode(unionAll) { OutputPath = codegenLookup.MatchPath });
unionAll.InputPaths.Add(new AstDataflowMappedInputPathNode(unionAll) { OutputPath = insertPlaceholder.OutputPath });
foreach (var outgoingPath in lookup.OutputPath.References)
{
if (outgoingPath.ReferencingItem != null && outgoingPath.PropertyName != null)
{
PropertyInfo propertyInfo = outgoingPath.GetType().GetProperty(outgoingPath.PropertyName);
if (propertyInfo != null)
{
propertyInfo.SetValue(outgoingPath.ReferencingItem, unionAll.OutputPath, null);
}
}
}
return unionAll;
}
private static AstLookupNode CreateLookupNode(AstLateArrivingLookupNode lookup)
{
var codegenLookup = new AstLookupNode(lookup.ParentItem)
{
Name = String.Format(CultureInfo.InvariantCulture, "__LALookupEntryPoint_{0}", lookup.Name),
Connection = lookup.Table.Connection
};
var requiredColumns = new List<string>();
foreach (var input in lookup.Inputs)
{
if (!requiredColumns.Contains(input.RemoteColumnName))
{
requiredColumns.Add(input.RemoteColumnName);
}
codegenLookup.Inputs.Add(input);
}
foreach (var output in lookup.Outputs)
{
if (!requiredColumns.Contains(output.RemoteColumnName))
{
requiredColumns.Add(output.RemoteColumnName);
}
codegenLookup.Outputs.Add(output);
}
codegenLookup.Query = new AstQueryNode(codegenLookup) { Body = TableLowerer.EmitSelectAllStatement(lookup.Table, requiredColumns) };
if (lookup.InputPath != null)
{
codegenLookup.InputPath = new AstDataflowMappedInputPathNode(codegenLookup) { OutputPath = lookup.InputPath.OutputPath };
}
return codegenLookup;
}