Transaction Isolation (contd.) 
The screenshot below shows result of SQL query of the table S1, and shows only the column (field) headers.

In this document, I enforced "COMMIT" after inserting some data in the table S1.

Now, refresh SQL developer, and you would note that the data added to the table S1 was realized and displayed, as shown in the screen-shot below.

Now open up SQL*Plus,

column fname format a10
column lname format a15
column address format a15
select * from s1;

Note in the above query, SQL reports the data the sync with SQL-Developer.