I’ll probably need this in the not-so-distant future. Here is the link to Noon’s write-up when I need it. His blog is recommended, by the way.
Friday I passed the OCP exam (1Z0-043). In two months I have studied for, and taken three tests in order to achieve OCP certification. Before I started on this in January I had noe previous experience with Prometric testing or certification at all. But I knew I had read a post about it earlier and started looking up an old post by Chen Shapira about how she prepared for the OCA exam. I ordered the same book as well as another book for the test that was added as an extra requirement for the OCA…
This year started off fine with a new job. I quit the company I joined just 25 months earlier, in itself a defeat. Though I gained much useful experience there, some signals convinced me to move on, and now I am quite happy that I did so. I joined Steria Norway to work as a senior system consultant, and so far it looks quite promising. The company is internationally focused and one is encouraged to build networks outside one’s country, something I find interesting. There is constant…
A couple of months ago I had an incident on a live production system. The obvious error was to execute a DDL statement at 9 am that should have been performed during off-business hours. On the other hand I guess you cannot avoid any ad hoc change on a live system forever. That will require you to be aware of any problem and issue that may strike your system. Say you have an issue right now, users are complaining, or to put it bluntly, someone is losing money. You think you have the solution, but…
A simple configuration with Oracle Connection Manager (CMAN) did not work, I constantly received ORA-12529 when trying to connect with sqlplus to a database through CMAN. After checking cman.ora over and over and browsing all the trace files I finaly dived into one and found a problem with host name resolving. Turned out that the host name defined in /etc/hosts on the database server was not known outside the server. The database, I assume, did a lookup on the ip number in local /etc/hosts and…
Today I was looking at an SQL statement with a slow response. The statement does a lookup on a person using ‘upper(lastname) and upper(firstname)’. There is a functioned-based index (fbi) on the lastname column, but by checking the statistics it turned out to have a rather low selectivity and the CBO went for a full table scan. I don’t know why it has not occurred to me before, but today it dawned upon me that it may be possible to create an index like this:
create index…
In a earlier post about legacy databases I mentioned that dirty data are more likely to enter the database on an earlier stage. One day while I was looking at the selectivity for a few columns I found the values a bit strange. After some digging I noticed that for most of the time the data was OK, even though a proper foreign key constraint was missing for the columns. But at some time many years ago somebody had inserted something completely different, which had clearly affected the selectivity…
I like great tools. An efficient tool will help you do a piece of work faster than when you are on your own. If the tool is made by someone who is close to the material chances are the tool is efficient. The tool I use most is SQL Developer. It is easy to use and I promote it to any developer where I work, especially if they only need a quick access to the data dictionary, run some simple (or complex) SQL statements. It is not invasive, contrary to other tools it does not provide all the DBA…
I have been working on a small scale data warehouse project for a few months along with many other tasks. Following Kimball’s ideas on dimensional modeling and by keeping it simple I had more or less an idea on how to proceed with the construction of the database, data model and how to create the reports (but only in SQL). One guy in management actually wanted to learn SQL and went ahead with SQL Developer (fantastic product, so easy to use that anybody familiar with the layout of the…
Just a short post on this error code. Happened last time I recreated a physical standby. I could not find more than the reference note on this error on Metalink (a note that is just a copy of the output from command oerr ora 16047):
