报ORA-06575 程序包或函数GETVALUEOFLX处于无效状态！求帮助

create or replace function GetValueOfLx (GV_constslsid in INTEGER,GV_constvalue in NVARCHAR2(100))
return NVARCHAR2(100)
is
GV_return NVARCHAR2(100);
begin
   GV_return ='';
   select GV_return:=consttrans from bdcs_constcls where
   constslsid=GV_constslsid and constvalue=GV_constvalue;

return GV_return;
end;
yqzd
执行select GetValueOfLx(8,'3') from sh 报错