public override void DetermineDataType(Plan plan)
{
DetermineModifiers(plan);
_dataType = new Schema.RowType();
foreach (Schema.Column column in SourceRowType.Columns)
{
DataType.Columns.Add(column.Copy());
}
_extendColumnOffset = DataType.Columns.Count;
plan.EnterRowContext();
try
{
plan.Symbols.Push(new Symbol(String.Empty, SourceRowType));
try
{
// Add a column for each expression
PlanNode planNode;
Schema.Column newColumn;
foreach (NamedColumnExpression column in _expressions)
{
planNode = Compiler.CompileExpression(plan, column.Expression);
newColumn =
new Schema.Column
(
column.ColumnAlias,
planNode.DataType
);
DataType.Columns.Add(newColumn);
Nodes.Add(planNode);
}
}
finally
{
plan.Symbols.Pop();
}
}
finally
{
plan.ExitRowContext();
}
}