private IQueryModel EnsureModel()
{
if (_model == null)
{
if (statement is SelectStatement stmt_sel)
{
_model = QueryModelLoader.LoadModel(batchResolver, "roooot", stmt_sel.QueryExpression, stmt_sel.WithCtesAndXmlNamespaces);
}
else
{
DataModificationSpecification source_specification = null;
DataModificationStatement stmt_mod = (DataModificationStatement)statement;
if (statement is InsertStatement stmt_ins)
{
source_specification = stmt_ins.InsertSpecification;
}
else if (statement is UpdateStatement stmt_upd)
{
source_specification = stmt_upd.UpdateSpecification;
}
else if (statement is DeleteStatement stmt_del)
{
source_specification = stmt_del.DeleteSpecification;
}
else if (statement is MergeStatement stmt_mrg)
{
source_specification = stmt_mrg.MergeSpecification;
}
_model = QueryModelLoader.LoadModificationOutputModel(batchResolver, "roooot", source_specification, stmt_mod.WithCtesAndXmlNamespaces);
}
}
return(_model);
}
public static EngineResult Evaluate(DataModificationSpecification dml, Scope scope)
{
IOutputSink sink;
// TODO: support scalar expressions in TableOutputSink, not just column names
// how to handle INSERTED. and DELETED. aliases?
if (dml.OutputClause != null || dml.OutputIntoClause != null)
{
sink = new TableOutputSink(
(dml.OutputClause?.SelectColumns ?? dml.OutputIntoClause?.SelectColumns)?
.Select(s => new Column
{
Name = ((ColumnReferenceExpression)((SelectScalarExpression)s).Expression)
.MultiPartIdentifier.Identifiers.Select(x => x.Value).ToArray(),
Type = DbType.AnsiString
}).ToList());
}
else
{
sink = new NullOutputSink();
}
var result = dml switch
{
InsertSpecification insert => Evaluate(insert, sink, scope),
MergeSpecification merge => Evaluate(merge, sink, scope),
DeleteSpecification delete => Evaluate(delete, sink, scope),
UpdateSpecification update => Evaluate(update, sink, scope),
_ => throw FeatureNotSupportedException.Subtype(dml)
};
if (dml.OutputIntoClause != null)
{
var(table, scope2) = Evaluate(dml.OutputIntoClause.IntoTable, null, scope);
Evaluate(
table,
dml.OutputIntoClause.IntoTableColumns,
((TableOutputSink)sink).Output,
new NullOutputSink(),
scope2);
}
return(dml.OutputClause != null
? new EngineResult(((TableOutputSink)sink).Output)
: result);
}
}
private OutputColumnDescriptor TryResolveColumnReferenceCoreSN(TSqlFragment node, string sourceNameOrAlias, string columnName)
{
OutputColumnDescriptor resultColumnType;
if (statement is SelectStatement stmt_sel)
{
if (TryQueryExpression(stmt_sel.QueryExpression, stmt_sel.WithCtesAndXmlNamespaces, sourceNameOrAlias, columnName, out resultColumnType))
{
return(resultColumnType);
}
return(null); // resolved failed!!!
}
if (statement is DataModificationStatement stmt_mod)
{
WithCtesAndXmlNamespaces source_ctes = stmt_mod.WithCtesAndXmlNamespaces;
DataModificationSpecification source_specification = null;
if (statement is InsertStatement stmt_ins && string.Equals(sourceNameOrAlias, "INSERTED", StringComparison.OrdinalIgnoreCase))
{
source_specification = stmt_ins.InsertSpecification;
}
else if (statement is UpdateStatement stmt_upd)
{
source_specification = stmt_upd.UpdateSpecification;
}
else if (statement is DeleteStatement stmt_del)
{
source_specification = stmt_del.DeleteSpecification;
}
else if (statement is MergeStatement stmt_mrg)
{
source_specification = stmt_mrg.MergeSpecification;
}
if (source_specification != null && source_specification.OutputClause != null)
{
if (TryTableReference(true, true, source_specification.Target, source_ctes, null, columnName, out resultColumnType))
{
return(resultColumnType);
}
throw new NotImplementedException("Target could not be found." + statement.WhatIsThis());
}
}
public QueryOnModificationOutputModel(int id, DataModificationSpecification mspec, string key)
: base(id, key)
{
MSpec = mspec;
}
public override void ExplicitVisit(DataModificationSpecification fragment)
{
_fragments.Add(fragment);
}
public QueryOnModificationOutputModel NewRootOnModificationOutput(DataModificationSpecification mspec, string key)
{
lastid++;
return(new QueryOnModificationOutputModel(lastid, mspec, key));
}
public sealed override void ExplicitVisit(DataModificationSpecification node)
{
base.ExplicitVisit(node);
}
public override void ExplicitVisit(DataModificationSpecification node) { this.action(node); }
