PSO elements and returnData option.

I agree that returning empty <psoID> elements (and empty <data> 
elements) is pretty bogus.
However, the XSD states that these elements are required.

ReturnDataType is used in two places: lookup and search. Neither of 
these operations really needs a 'none' option. I remember we had a use 
case for <lookupRequest returnData='none'> as a pure existence check, 
but returning a (possibly unwanted) <psoID> won't cause any harm.

However, we still have the problem of an empty <data> element when 
returnData='identifier'.
Should we also eliminate the 'identifier' value of ReturnDataType?
Or should we make the "data" element of PSOType optional?

Bohren, Jeffrey wrote:

> 3.5.7.1.2 Line 2649 states that if a PSO ID element must always be 
> present, then it states that if return data is specified as none, then 
> the PSO ID element would be empty. That would result in N number of 
> identical PSO ID elements, which wrong to me. I don’t see what that 
> would accomplish except being a very expensive way to do a server side 
> count. I would like to remove the none option completely.
>
> On line 2661 we state that if the option is none or identifier only 
> then the data element should be empty. That is not correct. In this 
> case the data element should be omitted. An empty data element should 
> never be present.
>