internal static ReadMapNode RenderMapNode(Workspace Home, int PartitionID, HScriptParser.Crudam_read_maprContext context)
{
// Get the data source //
DataSet data = VisitorHelper.GetData(Home, context.full_table_name());
string alias =
(context.K_AS() != null)
? context.IDENTIFIER().GetText()
: data.Name;
// Create a local heap to work off of //
MemoryStruct local_heap = new MemoryStruct(true);
// Create a record register //
StaticRegister memory = new StaticRegister(null);
// Create expression visitor //
ExpressionVisitor exp_vis = new ExpressionVisitor(local_heap, Home, alias, data.Columns, memory);
// Where clause //
Predicate where = VisitorHelper.GetWhere(exp_vis, context.where_clause());
// Create a reader //
RecordReader reader = data.OpenReader(where);
// Get the declarations //
if (context.crudam_declare_many() != null)
{
VisitorHelper.AllocateMemory(Home, local_heap, exp_vis, context.crudam_declare_many());
}
// Get the map actions //
ActionVisitor act_vis = new ActionVisitor(Home, local_heap, exp_vis);
act_vis.IsAsync = true;
TNode map = act_vis.ToNode(context.map_action().query_action());
// Get the reduce actions //
act_vis = new ActionVisitor(Home, local_heap, exp_vis);
act_vis.IsAsync = false;
TNode red = act_vis.ToNode(context.reduce_action().query_action());
ReadMapNode node = new ReadMapNode(PartitionID, map, red, memory, where);
return node;
}