string type_name = schema->get_type_name(tbl_vec[0]->get_schema_ref(),field);
param_list *modifiers = schema->get_modifier_list(cr->get_schema_ref(), field);
data_type *dt0 = new data_type(type_name, modifiers);
string type_name = schema->get_type_name(tbl_vec[0]->get_schema_ref(),field);
param_list *modifiers = schema->get_modifier_list(cr->get_schema_ref(), field);
data_type *dt0 = new data_type(type_name, modifiers);