Category Archives: DBA

Strange behavior in MERGE with sequence NEXTVAL

Today we learned the following: “When using a sequence in a MERGE statement, the nextvalue is generated for all rows both updated and inserted (hence all rows in the source).” Our initial reaction was that this must be a bug, but is it really?

SQL Developer, Database Copy and TRUNCATING unwanted tables

I just experienced something scary with SQL Developer and the “Database Copy” utility. One table in production was truncated by a mistake. I have always been a little against using the SQL Developer functionality “Database Copy …” in production, but for this one task during deployment of a new release, this customer (including me) have […]

Nice blog about DBMS_METADATA from Alex Nuijten

This blog post has been laying in my TO_READ folder for a long time. Finally found some time to catch up, and I especially liked the little piece of PL/SQL for remapping the schema.

OOW16 – Are we failing or will performance rise?

The last session I attended at OpenWorld 2016 was “Thinking Clearly About Database Application Architecture”. A panel discussion with Toon Koppelaars, Cary Millsap, Gerald Venzl, Bryn Llewellyn and Connor Mcdonald. The panelists promotes that the business logic should be moved into the database, and implemented using PL/SQL. And yes – I do get the message, but I just […]

An Oracle DBA at JavaZone – a fish on land?

Why in the world should an Oracle DBA spend two workdays at a Java conference like JavaZone. It doesn’t matter if the JavaZone is the third biggest Java conference in the world, serve great food all day long, have a concert at night with awesome bands, and – of course – you get a couple […]

One of the things you just need to know about Oracle …

A couple of years ago I did ask my developers to start using the varchar2(char) option when creating new tables. In Norway we have some characters in the alphabet (‘Æ’, ‘Ø’, ‘Å’) that uses more than 1 byte of storage (when the database characterset is set to AL32UTF8). Using the default – varchar2(byte) – could then decrease the number […]

Template for creating data owners and application users

How many times haven’t I seen applications logging onto the Oracle database as the schema owner. This is definitely not good practice. And usually by the time the DBA discovers this, it’s “to late” to change. I’ve heard managers say: “It will be to expensive and to much of a risk changing this now”. (Note! […]

I’m speaking at Oracle OpenWorld 2014, San Francisco, in September/October

I’ve just registered in this years OpenWorld conference in San Francisco in september. Last time I attended was in 2012. The news this year is that I’m going to be a speaker. My call for paper “Performance doesn’t happen by accident: Database performance for DBAs” just got accepted. Look for session id CON1918. Hope to see […]