Data structure of an OLAP cube

1
votes

MDX newbie here. I'm trying to imagine the data structure of an OLAP cube. Here's my basic idea:

  • the cube is a collection of data items
  • each data item contains a set of numeric values that correspond to measures (some might be null)
  • each data item optionally contains a record for every dimension of the cube; that record contains fields that correspond to dimension attributes.

Is that a valid mental model?

2
mdxolapolap-cube
sounds like a reasonable way to visualize it - I think a lot of folks visualize a cube (because any further dimensions would be tricky!) and then think about slicing the cube up, or pintointing certain bits of the cube - whytheq
I'd say it collects (generates) coordinates (aggregated data value) for an every possible slice of the cube. - Danylo Korostil

2 Answers

1
votes

Some people (I know I do) use a cube as a visualization model method:

enter image description here

I realize it only covers 3 dimensions but that is about all most of us can think about !

0
votes

a very interesting discussion. The cube is already an abstraction, a conceptual representation of a data model. So, if you imagine a cube, you already imagine an OLAP data structure at a high level of abstraction. I may add that each cell of the cube stores a numerical value (measure) pointed out by a set of coordinates (dimensions), which are not optional. On turn, a dimension can be organized in aggregation levels that form a hierarchy.