ORA-12838

If you do an INSERT /* APPEND */, you cannot query the table afterwards until you have done a COMMIT. If you try to do so, Oracle gives you an ORA-12838. You can see what I mean in the example below, which I tested on Oracle 11.2:

SQL> create table tab1

  2  as select * from dba_tables

  3  where 1 = 2

  4  /

 

Table created.

 

SQL> insert /*+ append */ into tab1

  2  select * from dba_tables

  3  /

 

3166 rows created.

 

SQL> select count(*) from tab1

  2  /

select count(*) from tab1

                     *

ERROR at line 1:

ORA-12838: cannot read/modify an object after

modifying it in parallel

 

SQL> commit

  2  /

 

Commit complete.

 

SQL> select count(*) from tab1

  2  /

 

  COUNT(*)

----------

      3166

 

SQL>