What does the ASH column TOP_LEVEL_SQL_OPCODE decode to?

Question

Oracle Database 11g Enterprise Edition Release 11.1.0.7.0 - 64bit Production running on Linux x64
Does anyone have the decoding for the TOP_LEVEL_SQL_OPCODE in V$ACTIVE_SESSION_HISTORY ?
The server reference says "Indicates what phase of operation the top level SQL statement was in"
Does anyone know if this is meaningful data?
Here is an example from my system:
SQL>select ash.TOP_LEVEL_SQL_OPCODE, count(
  2  from v$active_session_history ash
  3  group by ash.TOP_LEVEL_SQL_OPCODE
  4  order by 2 desc;
TOP_LEVEL_SQL_OPCODE   COUNT(*)
                   3      23981
                  47       9191
                 189       7840
                   0       6450
                   6       5937
                   2        278
                   7        144
                 170         71
                  97         70
                  96         11
                  55         10
                  94          9
                   1          7
                   9          4
                  85          1
                 174          1
                  15          1
                  12          1

Answer 1

is this making sense?
SQL> select action, name from audit_actions
  2  where action in ( 3,47,189,0,6,2,7,170,97,96,55,94,1,9,85,174,15,12);
    ACTION NAME
         0 UNKNOWN
         1 CREATE TABLE
         2 INSERT
         3 SELECT
         6 UPDATE
         7 DELETE
         9 CREATE INDEX
        12 DROP TABLE
        15 ALTER TABLE
        47 PL/SQL EXECUTE
        55 SET ROLE
    ACTION NAME
        85 TRUNCATE TABLE
        94 CREATE PACKAGE
        96 DROP PACKAGE
        97 CREATE PACKAGE BODY
       170 CALL METHOD
       174 CREATE DIMENSION
17 rows selected.Amiel