SQL> desc prc.ax_log;
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------
 TRANS_ID                                  NOT NULL VARCHAR2(255)
 ACCESS_TIME                                        DATE
 IP                                                 VARCHAR2(16)
 MAIL_FROM                                          NVARCHAR2(255)
 MAIL_SUBJECT                                       NVARCHAR2(255)
 MAIL_SIZE                                          NUMBER(38)
 POLICY_ID                                          NUMBER(38)
 FILTER_ID                                          NUMBER(38)
 MAIL_FLAG                                          NUMBER(38)
 PROTOCOL_TYPE                                      NUMBER(38)
 SCORE                                              NUMBER
 INSERTTIME                                NOT NULL DATE
 ATT_COUNT                                          NUMBER(38)
 USER_ID                                            VARCHAR2(60)
 ISCOMPUTED                                         NUMBER(1)
 MONTHNO                                   NOT NULL NUMBER(6)
 PROVCODE                                           NUMBER(3)


SQL> Select *
  2    From prc.ax_log
  3   Where Inserttime >= Trunc(Sysdate - 1)
  4     And Inserttime < Trunc(Sysdate)
  5     And User_Id Is Not Null
  6     And Length(User_Id) > 20;
  From prc.ax_log
                    *
ERROR at line 2:
ORA-08103: object no longer exists

08103, 00000, "object no longer exists"
// *Cause:  The object has been deleted by another user since the operation
//          began, or a prior incomplete recovery restored the database to
//          a point in time during the deletion of the object.
// *Action: Delete the object if this is the result of an incomplete
//          recovery.