Hi Mike,
Maybe I should 'my database is slow' with 'my environment is slow'.
The first fact that make me think my operations are not running in an optimal way were 'dumping a 361Gb DB' and dropping such DB.
Again the dump took almost two hours and that seems long for me. I have another server with 230Gb database and the dump took about 40 mins.
Next is a update statement on one table with self join executed on monday night that took 10 hours.
the table impacted are quite big (bout 4.6 millions rows) and the showplan pointed out two table scan on the same table, this could explain the duration of the execution (see below for the plan).
So for this example I believe the SQL should be reviewed but my approach I'd like to set up is if "people are complaining about application slowness"
1.let's find out if the slownesses are coming from the application layer or the DB layer
2.If the slowness is on the DB layer, let's make sure the dataserver and machine hosting the dataserver are correctly set.
3. If 2. is correct then let's review the guilty statements.
My main activity is about migrating a database so I know it'll be CPU and IO intensive at DB level, this is why for the last point I'd like to find a way that the IO settings are set correctly.
Thanks all for your feedback.
Simon