zoom: return diagnostic if CQL sortby conv fails. Diagnostic Bib-1 214
"Illegal sort relation" is returned. Gets translated to SRU diagnostic
90: "Unsupported direction value".
zoom: return diagnostic if CQL sortby conv fails. Diagnostic Bib-1 214
"Illegal sort relation" is returned. Gets translated to SRU diagnostic
90: "Unsupported direction value".