SQL Developer - Selects

Hi together,

some questions about SQL Developer and how it is working with the
database...

When I open a datatable (tab data), SQLD does a coresponding select on
the table. Looking at enterprise manager i see that the select
consists out of ORA_ROWSCN and all the columns from the table. In a
table with million records i get an instant result cause only 55 rows
in my case are fetched. When i take the same select and execute it,
it would take much longer cause i get the whole table. How is it
possible to limit the number of records in the result with such a
select?
Is the result from such a select from the same point of time?
When i change sorting SQLD makes a new select statement.

Another question little bit offtopic is it possible to see a live
trace of a oracle session for example like tail, all the statements
from one session live?

Thanks for your time.. :)

Markus

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