Well, it's a performance issue. Our development databases are in AWS, so it would be more efficient to bring everything in larger chunks. For instance, using SQL*Plus:
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
SQL> SET TIMING ON
SQL> SET AUTOT TRACEONLY STATISTICS
SQL> select * from kiprev.fo_cuentas where rownum < 5000;
4999 rows selected.
Elapsed: 00:00:58.42
Statistics
----------------------------------------------------------
...
800392 bytes sent via SQL*Net to client
4139 bytes received via SQL*Net from client
335 SQL*Net roundtrips to/from client
...
SQL> SET ARRAYSIZE 1000
SQL> select * from kiprev.fo_cuentas where rownum < 5000;
4999 rows selected.
Elapsed: 00:00:08.17
Statistics
----------------------------------------------------------
...
772098 bytes sent via SQL*Net to client
520 bytes received via SQL*Net from client
6 SQL*Net roundtrips to/from client...
As you can see, the time spent and the number of roundtrips drop dramatically.
The Command Window accepts setting ARRAYSIZE, and maybe the SQL Window does too, but the problem for me are all the things brought by sessions I cannot control. The main issue are large packages; plsqldev is taking several minutes to open the code in a Program Window.
In both TOAD and SQLDeveloper you can set the arraysize, so I guess it's something you can pass to the OCI libraries when requesting a connection.