SQL> create table tbl(val anydata)
  2  /

Table created.

SQL> insert
  2    into tbl
  3    values(anydata.convertvarchar2('String'))
  4  /

1 row created.

SQL> insert
  2    into tbl
  3    values(anydata.convertnumber(12345))
  4  /

1 row created.

SQL> insert
  2    into tbl
  3    values(anydata.convertdate(sysdate))
  4  /

1 row created.

SQL> commit;

Commit complete.

SQL> select  count(*)
  2    from  tbl t
  3    where 'String' = t.val.accessvarchar2()
  4  /

  COUNT(*)
----------
         1

SQL> select  count(*)
  2    from  tbl t
  3    where 12345 = t.val.accessnumber()
  4  /

  COUNT(*)
----------
         1

SQL> column VAL_TYPE format a20
SQL> column val format a30
SQL> select  *
  2    from  tbl
  3  /

VAL()
------------------------------
ANYDATA()
ANYDATA()
ANYDATA()

SQL> select  t.val.gettypename() val_type,
  2          case t.val.gettypename()
  3            when 'SYS.VARCHAR2' then t.val.accessvarchar2()
  4            when 'SYS.NUMBER' then to_char(t.val.accessnumber())
  5            when 'SYS.DATE' then to_char(t.val.accessdate(),'MM/DD/YYYY HH24:MI:SS')
  6          end val
  7    from  tbl t
  8  /

VAL_TYPE             VAL
-------------------- ------------------------------
SYS.VARCHAR2         String
SYS.NUMBER           12345
SYS.DATE             10/18/2019 10:24:23

SQL>