At work, on the production server, when I changed a view, it hung for a while and I had to kill it because DBAs told me it caused some blockings. I think other processes were running/waiting to run that view . ( it should be similar to the case when we are using a package and trying to recompile it, shouldn't it ? ).
On my home PC, I open two sessions, the first one runs "select * fron my_test_vw" which runs in a long time due to the underlying table has millions of records. At the same time on the second session I execute "create or replace view my_test_vw ..." to change its exposing columns. I thought it should hang waiting for my first session finishing, but the command executed successfully immediately while the other session is still running.
Then, what might have caused my view change at work hung ?
Thanks,
Vu