Hello experts,
I have a simple question regarding rebuilding indexes...
First, I am running 11.2.0.2 on Solaris 10.
My reason for rebuilding is to relocate the indexes to their own tablespace, and while I recognize this is a subjective reason as far as performance is concerned, it makes administration easier.
That being said, my question is in regards to use of "compute statistics" and also "online", and "nologging".
Since I do want to minimize he impact to our users, and this table is one of the most used tables in the database, my syntax was going to be as follows:
alter index <schema>.<index> rebuild online nologging tablespace <ts_idx> compute statistics;
Questions:
1. does doing the rebuild online preclude queries against the table during the duration of the rebuild?
2. does use of nologging improve speed of rebuilding
3. is it advisable to include the "compute statistics". I believe I read on Jonathan Lewis' page that statistics are gathered automatically and to include "compute statistics" was not necessary when rebuilding an index.
And I guess one final question is whether I can include all the options in the same rebuild statement as I have shown above?
I've tested the above in our test database, but it seems to hang when using the online option (with all the other options).
Thanks in advance.