隐藏参数 (hidden parameters) ,由oracle内部使用,以 ‘_’ 开头。
cat > hidden_param.sql
set line 999
col ksppinm format a50
col ksppstvl format a50
col ksppdesc format a50
SELECT ksppinm, ksppstvl, ksppdesc
FROM x$ksppi x, x$ksppcv y
WHERE x.indx = y.indx AND ksppinm = '&hidden_parameter';
@hidden_param.sql