Oracle Autonomous Data Warehouse Cloud does not allow to create indexes. Is this a problem for star schemas because no Star Transformation can be used? Or are the required bitmap indexes automatically created? A look under the hood of ADWC.
Category Archives: Dimensional Modeling
My Sessions at DOAG 2017
This year, I had the opportunity to present three sessions at the DOAG conference in Nuremberg – one on each conference day. Here a short summary of the sessions and links to the downloads.
Analytic Views: Powerful Oracle 12.2 Feature for Business Intelligence
Analytic Views are one of the main features for Business Intelligence introduced with Oracle 12c Release 2. They provide a lot of new possibilities for analytical queries on star schemas. This blog post gives an overview of the new functionality.
Attribute Dimensions and Hierarchies in Oracle 12.2
Oracle 12c Release 2 introduced Analytic Views, a new set of metadata objects that are very useful for Data Warehouses and Business Intelligence applications. In the first blog post about this new feature I will have a detailed look at two of the new object types: Attribute Dimensions and Hierarchies.
Derived Measures and Virtual Columns
Virtual Columns in Oracle are a convenient feature to implement derived measures of a fact table. But in combination with Oracle Database In-Memory, it has an impact on performance – unless you use Oracle 12c Release 2.
Loading Dimensions from a Data Vault Model
Loading data into a Data Vault Model is easy. But how complex is it to extract the data from a Data Vault into a dimensional Data Mart? A Point in Time (PIT) table helps to load Dimensions from a Hub with multiple Satellites.
Reference Partitioning on Star Schema: A Good Idea?
In my last blog post, I noticed that surrogate keys on a time dimension cannot be combined with partitioned fact tables in a star schema. Actually, there is a way to do that: With reference partitioning it is possible to implement monthly partitioned fact tables based on a surrogate time key. But is this a good idea?
Time Dimension Keys and Partitioning
In the physical design of a star schema, it is recommended to use surrogate keys for the primary keys of dimension tables. Except for the time dimension. In Oracle data warehouses it is common to use a DATE column as the primary key. The reason for this decision and several alternative solutions are described in this post.
My Conference Presentations on Slideshare
The Oracle OpenWorld 2014 just finished yesterday, but unfortunately I was not able to attend this great conference this year. Perhaps next year – who knows…
But I had the luck to give several presentations in the last few years on Oracle OpenWorld in San Francisco, on the DOAG Conference in Nuremberg and on some other German conferences. Now you can find all these presentations on SlideShare. Because most of the slides are not brand new, my Trivadis colleague Silvana Bernasconi reformatted the older presentations to the current Trivadis PowerPoint template (thank you, Silvana). Nevertheless I promise: The contents of all these presentations is still up to date. Enjoy to have a look at and probably download some of the presentations.
An overview of all my presentations you can find on the Presentation page.
The perfect Data Modeling Method that fits for all Data Warehouses…
…does not exist. Each Data Warehouse is different. Not only the known (or unknown) analytical requirements and the number, complexity and structure of the source systems have an impact on the architecture and design of a Data Warehouse.