Oracle Database Discussions

Hi ALL,

I started gathering database stats on database(oracle 11.2.0.3,OS Solaries) by using dbms_stats.gather_database_stats(estimate_percent=>100,degree=>32).

Suddenly my DB performance decrease during stats gathering and when i check in AWR ,SQL like
"
*select /*+ parallel(t, 32) parallel_index(t, 32) dbms_stats cursor_sharing_exact use_weak_name_resl dynamic_sampling(0) no_monitoring no_substrb_pad */count(*) ***********

"
are running and coming in 'SQL ordered by Elapsed Time ,SQL ordered by CPU Time '.

But what make surprise is that all the columns in SQL are my table column and from clause also reference my table name.All columns in the above SQL statement using some sql functions.

Now my question is that during stats gathering process Oracle internally fire these SQL or these are user SQL.

Please inform me any other information is required.
Thanks in advance to all.