I am attending Percona Live Amsterdam 2015 on September 21-23, 2015.

I will be on stage three times:

• September 22nd at 2:10pm Pivot tables: analytics in pure SQL
• September 23rd at 2:10pm The future of replication is today: new features in practice
• September 23rd at 5:10pm as host and speaker in the Lightning talks

My first talk is a topic that has ben among my favorites for long time: I published an article about it in 2001, and several …

A couple of months ago I wrote about how you can use the MDX functions Ancestors() and Ascendants to retrieve the full lineage of members. (See: "MDX: retrieving the entire hierarchy path with Ancestors()".)

As you might recall, the immediate reason to write about those functions was to find a pure MDX solution to implement the "Show Parents" / "Hide Parents" functionality offered by OLAP cube browsers. To recap, developers of MDX-based pivot tables face a challenge when rendering the result of a query like this:

SELECT    CrossJoin(
            [Product].[Product].Members,
 …

A crosstab query is a specific query used to create aggregate reports on two or more fields, it’s  a handy way to display summary information. At Open Query we have customers using that trick to display production schedules.

The summary table is generated from the database to extract the manufacturing date (mand), unit number (unitn), product area (pro_area), and ranking (rnk). Then we can start using that summary table to process our crosstab. The summary table looks like this:

Some background is needed. Crosstabs (also called data cubes or pivot tables, have been one of my favorite hacks for long time. In 2001 I wrote an article about a simple …