A big conference like Oracle Open World is an excellent opportunity to learn more. But with all the books, blog posts, and on-demand learning on Internet, I really did not have to go to OOW this year to keep myself busy learning. Of course, I learned a lot, but for me, the biggest reward is the inspiration and ideas for future projects, as well as meeting friends in the community including Oracle employees who take part in it. ...

The biggest conference for Oracle users in the Nordics is not far away. Be there as a speaker and attendee. Sure you have a war story or another experience worth sharing. Last year OUGN received 250 abstracts, please, do it again! Follow this link to submit your abstracts: http://c4p.ougn.no/ Deadline is November 15. See you on the ship (which is a boat with other boats on it, according to Millsap)!

I have my mental list of people in the Oracle community I look up to. They are people who help through social networks, emails, presentations, books, blog posts, or in a friendly conversation. Now, Oracle has recognised that there are many such individuals in the community, people that know a lot and spend much time sharing it with others. In fact they have asked us to vote on our developer heroes, and they will award them during a big celebration at Oracle Open World. Sure you have met one SQL guru, or a PL/SQL programmer, or someone really concerned about database design? Since I am a DBA I think that we should support our database developers since they are doing their part to make sure that the database, and database application that we will support later is as good as possible. ...

In case you do not want to grant a user access to data dictionary tables like DBA_TABLES, but will let user B see the list of all tables belonging to user A, you can work around it with a pipelined function in schema A: create type str_set as table of varchar2(30); / create or replace function a_tables return str_set pipelined is l_str varchar2(30); begin for l_str in (select table_name from user_tables) loop pipe row(l_str.table_name); end loop; return; end; / grant execute on a_tables to B; Then user B can see the list of A’s table with: ...

When you run dbms_stats.gather_table_stats on tables with spatial indexes or dbms_stats.gather_index_stats directly on the spatial index the routine may return without an error even if no statistics gathering took place. You can verify this by looking at the LAST_ANALYZED column in DBA_INDEXES: select owner,index_name,last_analyzed from dba_indexes where index_type='DOMAIN'; Another way to verify if statistics gathering for these indexes took place is to look for tables with names that start with MDXT: ...

When you need to find the OS-process on the database server for an oracle session (dedicated server) you can join v$session with v$process: select p.spid from v$session s join v$process p on(s.paddr=p.addr) where s.sid=42; But if you kill a session with ‘alter system kill session …’ the link between these views are broken because the value in v$session.addr changes. In order to look for these orphan processes run this query: select spid, program from v$process where program!= 'PSEUDO' and addr not in (select paddr from v$session) and addr not in (select paddr from v$bgprocess) and addr not in (select paddr from v$shared_server); You may check with OS tools like ps on Linux to see that these are indeed dead processes or with strace to see what they are doing and eventually kill them.

When I had my first Oracle DBA course some years before the start of this millennium I made a special mental note about a very common error message, ORA-00942, “table or view does not exist”. In most programming languages there are a similar message for a common situation; when you refer to an object that does not exist, quite often because you wrote the name wrong. What I found a bit remarkable when I heard about it first time was that ORA-942 may mean two things, either that the table or view does indeed not exist, or you do not have access to it. An example of the latter is when some user has created a table in her schema, and you try to query it, but you have not been granted a privilege to do so. Instead of you receiving some error message like “access denied”, Oracle responds with the same error message; “table or view does not exist”, even if it does exist. It may have added “for you” to make it more correct. I think there is a good reason why this is so, and I think it has to do with optimisation. ...

Should be obvious, but I just discovered that it is much easier to change preferences if you search for it in the search field instead of wandering around in the Preferences GUI looking for the place where you can set it: And it is pretty fast, try to look for the place where you choose the OCI client, just write OCI in the field. And similarly, if you think you wrote some smart code a few days ago, just search for it in the SQL history: ...

Here the other day I came across this package in a PL/SQL procedure written by someone else. From the name I reckoned it was a standard package from Oracle, but I had never seen it before. It is not mentioned in the manual Database PL/SQL Packages and Types Reference, and I could not find much about it at My Oracle Support either. Anyway, with SQL Developer you’ll get what you need by hitting Shift-F4 (with the cursor at the name of the package). The API is pretty good documented in the comments. The package is used to rebuild indexes, either for a named table, a named schema, or a list of indexes plus some stuff I didn’t bother to look into. ...

At UKOUG Tech conference in Liverpool last year I had an interesting talk with a DBA that had two years of experience. Being 23 years the DBA naturally stood out from the crowd. I talked about my thoughts on what is important for a DBA, and since I spend way too much on user group activities and conferences I argued that going to such events are useful for a DBA, and continued with other ramblings about what I think is important for a DBA to do. I hope I stopped soon enough, but stop talking and start listening is an art. Anyway, I decided to write down a list of recommendations for a new DBA. This is what I think is important. ...