Kim Berg Hansen

Middelfart, Denmark

Kim Berg Hansen is a database developer from Middelfart in Denmark. Originally wanting to work with electronics, he almost coincidentally tried computer programming and discovered where his talent lay, as the programs he did worked well – unlike the electronics projects he soldered that often failed. After that experience he progressed from Commodore Basic on VIC-20 over Modula-2 and C at Odense University to Oracle SQL and PL/SQL, which last two languages he now has worked with extensively since the year 2000. His professional passion is to work with data inside the database utilizing the SQL language to the fullest to achieve the best application experience for the users.

Kim shares his experience and knowledge by writing the Practical Oracle SQL book, blogging, presenting at various Oracle User Group conferences, and being the SQL quizmaster at the Oracle Dev Gym. His motivation is when peers go “now I understand” after his explanations, or when end users “can’t live without” his application coding. He is certified Oracle OCE in SQL as well as awarded Oracle ACE Director. Outside the coding world Kim is married, loves to cook, and is a card-carrying member of Danish Beer Enthusiasts association.

Analytic Functions 101

Plain SQL gives you either detailed single rows or aggregated data. When you need both, or need in one row to get data of other rows, you tend to do self-joins or slow procedural processing. Instea...

Analytic Functions in Real Life

When you learn the basics of analytic functions, most often you will see nice short examples. You may then have problems translating those basics into useful code for your real work. In this sessio...

Analytic Views in Oracle Database 12.2: The Virtual Cube

Dimensional analysis of data traditionally means copying data to a cube, as the realtime alternative is lots of advanced SQL. In Oracle 12.2 that became a lot easier with analytic views, where the ...

Data Twisting

Quite often you have data in rows and need them in columns, or vice versa. You can also often have delimited data in strings and need them separated out, or conversely aggregate rows of data into d...

External Tables - Not Just Loading a CSV File

With external tables you can SELECT from files - great for loading plain CSV files, but it can do so much more than that. Learn about loading from text files, DataPump dump files, HDFS and HIVE, as...

Forecasting in Oracle using the Power of SQL

You have many options for analyzing your data, for example in R. But Oracle Database and SQL can do a lot of directly. So is specialized tools like R or good old SQL preferable? We use Forecasting ...

Invitation to the Wedding of JSON and Relational Data

"The happy Data couple cordially invites you to the Wedding of Mr. JSON and Ms. Relational." Mr. JSON began courtship in Oracle version 12.1.0.2 to the delight of Ms. Relational. In every Oracle v...

JSON in Oracle Database version 12.2

Oracle database 12.2 works well with JSON, both querying and creating. You can search in the JSON and index it, integrate GeoJSON with Spatial, and generate JSON from your relational data. The data...

OK Oracle, Tell Me Approximately How Many Unique Visitors We Had Last Week

Statistical overviews often use distinct counts, medians and percentiles. On larger datasets they might take more time than the users like. But often approximate answers are "good enough" if they c...

PowerHauling Data with PowerShell

There are many ways of migrating data between databases, even between different database vendors. PowerShell scripts can be a useful method, and if the target database supports bulk copy classes (f...

Shape-Changing SQL

There's static SQL and dynamic SQL, but in between there's also SQL that's "dynamic at parse-time" (but not at runtime) - also known as polymorphic (meaning it can change "shape".) This talk looks ...

Uses of Row Pattern Matching

Row pattern matching is useful for recognizing patterns in rows of data, as the name implies. But the uses of MATCH_RECOGNIZE extends beyond the obvious - it can be applied to grouping consecutive ...

Ways to the Bacon

Is Bacon something you eat or calculate? Both. The Bacon Number of an actor is the lowest degree of separation from Kevin Bacon defined by linking via actors appearing in same movie cast. How to ca...

When 7-bit ASCII ain't enough - about NLS, Collation, Charsets, Unicode and such

A-Z in upper and lower case isn't enough in a global world, you need to support all sorts of textual data. Oracle database can handle most of it, but there are pitfalls to be aware of - even using ...

Who's Afraid of the Big Bad SQL?

Developers often treat a database as a bit bucket, processing data procedurally or using an ORM. Doing the same processing in SQL can be unfamiliar. I'll compare the two and show that SQL is not sc...