GV$SQLFN_ARG_METADATA definition in Oracle Database 11.2
GV$SQLFN_ARG_METADATA
select
inst_id, -- INST_ID NUMBER
id, -- FUNC_ID NUMBER
argnum, -- ARGNUM NUMBER
case -- DATATYPE VARCHAR2(8)
when dtype = 0
then 'UNKNOWN'
when dtype = 1
then 'NUMERIC'
when dtype = 2
then 'STRING'
when dtype = 3
then 'DATETYPE'
when dtype = 4
then 'BINARY'
when dtype = 5
then 'EXPR'
when dtype = 6
then 'ARG 1'
when dtype = 7
then 'ARG 2'
when dtype = 8
then 'ARG 3'
else 'INVALID' end,
descr -- DESCR VARCHAR2(30)
from
x$oparg