CubeSlice, by SDG Computing, Inc.office (715) 262-3601

The Different Local Cube Creation Syntaxes in AS2005/AS2008

Local cubes created from the two forms of ASSL used by CubeSlice are very similar, though local cubes created with CubeSlice Relational ASSL can be superior. In certain situations they will be smaller and will have faster browsing performance.

Here is a detailed description of the differences:

1. Local cubes created with CubeSlice Relational ASSL are usually (but not always) smaller than local cubes created with CubeSlice OLAP ASSL.

In the following situations, the size difference can be very significant:
  • The size of CubeSlice Relational ASSL cubes can be significantly reduced by changing the dimension keys of large dimensions. It is not possible to change the dimension keys when using CubeSlice OLAP ASSL cubes.
  • When including ROLAP dimensions in the local cube, the CubeSlice Relational ASSL local cubes can be significantly smaller.

2. Local cubes created with CubeSlice OLAP ASSL can have slower browsing performance when certain features are included in the local cubes.

Here are the features that can slow browsing in a CubeSlice OLAP ASSL local cube:
  • Unary operators
  • Custom rollup formulas
  • Measures with Distinct Count aggregation
  • ROLAP dimensions

3. CubeSlice Relational ASSL cubes can have more up-to-date data, because they are created from the current relational data, while CubeSlice OLAP ASSL cubes are created from Analysis Server cubes, with data current as of the last time the server cube was processed.

4. When unary operators are used along with measures using semi-additive aggregations, the data in the local cubes can differ.

This happens in the following situation:
  • Unary operators are being used
  • A semi-additive measure (such as Most Recent Non-Null Value) is being used
  • There is no data for a time period in the source data, so that a previous value is displayed in the cube.
In this situation the CubeSlice Relational ASSL local cube ignores the value in the semi-additive measure and does not include it in aggregations, matching the behavior in the Analysis Server cube. The CubeSlice OLAP ASSL local cube uses the value in the semi-additive measure and aggregates it into the higher levels using the specified unary operator.