Is it possible to see the (completed) SQL Statements executed by a specific session

There are a few different approaches depending on the details of your batch process and why you're trying to view the uncommitted changes.

1) Oracle Workspace Manager is a tool that was originally designed to allow people developing Spatial applications to have the equivalent of extremely long-running transactions (i.e. transactions that may require multiple days or weeks of humans figuring out where to run a pipeline in one transaction). Your batch process could create a new workspace (which is logically like creating a new transaction), make whatever changes it would like in that workspace while committing whenever it wanted. In a separate session, you wouldn't see any of the committed changes until you entered the batch process's workspace. When the batch process finished, it could merge it's workspace back into the live workspace which is the equivalent of committing a transaction.

2) The DBMS_XA package can be used to allow you to "hand off" a transaction from one session to another and to allow one session to connect to a transaction started by another session. This is a pretty obscure package to be using, but there was a nice example of using it in the PL/SQL Challenge (you may need a free account to access it) recently.

3) If you're just trying to see the status of the batch process rather than seeing the actual data, the batch process can write logging information using autonomous transactions that you could then query from another session. Or you could use the DBMS_APPLICATION_INFO package to have your application update various attributes in V$SESSION and/or V$SESSION_LONGOPS so that you could monitor the status of the load from another session.

In a shell script:

#!/bin/bash

sqlplus user/pass@server/DATABASE<<THEEND

-- Change "1" to the desired fatal return code

whenever sqlerror exit 1;

@yoursqlscript.sql

quit;

THEEND

Or you can just run:

sqlplus user/pass@server/DATABASE @yoursqlscript

... and put the whenever sqlerror exit 1; at the top of your .sql script(s).