public NestedCommand Select(string requestPath)
{
var _requestPath = new EntityPath(from.root.Entity.ID, requestPath).Path;
var p = SelectCommandHelper.ValidatePath(_requestPath);
(string[], string)item;
if (p.Count() > 1)
{
throw new ArgumentException("Only one field should be returned by sub queries");
}
else if (p.Count() == 0)
{
throw new ArgumentException("At least one field should be returned by sub queries");
}
else
{
item = p.First();
}
if (item.Item2 == "*")
{
throw new ArgumentException("Select all not allowed in sub queries.");
}
outputField = SelectCommandHelper.GenerateSingleSelectNode(item, from);
return(this);
}
internal override void ParseSQL()
{
base.ParseSQL();
// if no output field specified use the primary key as fallback
if (outputField is null)
{
outputField = new SelectNode()
{
FullPath = new FieldPath(from.root.Entity.ID, from.root.Entity.ID, from.root.Entity.PrimaryKey.CodeName),
EntityField = from.root.Entity.PrimaryKey,
FromNode = from.root
};
}
base.query.Select($"{outputField.Alias}.{outputField.DBName} AS {outputField.Alias}${outputField.CodeName}");
}