what is the diffrence between regular and alias shortcut in FM?

[bvk.cognoise]

HI,

i know the diffrence between alias and regular shoretcut.but my question  is in whch situation we use regular shortcut,in whch situation we use  regular shortcut.


thanks for ur reply in advance

BVK

[rockytopmark]

I assume you mean Reference shortcut, when you write "Regular" since Reference and Alias are the 2 types of shortcuts in Cognos.

Reference Shortcuts are commonly used when building your Presentation Layer's Star Schema Groupings (Focused Namespaces).  The Facts and Dimensions are defined in the Development Layer, then "Referenced" in the Presentation Layer. (Presentation Layer ideally will ONLY contain shortcuts)

Alias shortcuts are usually found in the same namespace as the original, and are used for multiple roles being played by a single physical dimension, such as the TIME dimension.  For example, an Order Fact may have and Order Date, a Shipped Date and an Invoice Date.  These 3 roles would require 3 separate iterations of TIME dimensions be modeled for each specific role.

HTH, M

[mvoosten]

Try creating a shortcut on an alias with independent join paths.. so much for independence.. Select go to target and you will see it will still reference the original query subject. When using a shortcut on an alias in your report (shortcut in presentation view from alias in business view for example), the joins will be ignored!!

[cognostechie]

Try creating a shortcut on an alias with independent join paths.. so much for independence.. Select go to target and you will see it will still reference the original query subject. When using a shortcut on an alias in your report (shortcut in presentation view from alias in business view for example), the joins will be ignored!!

You are narrating a scenario where you have joins in BOTH Business View and Database View. In that case, the joins of Database View will be ignored. This is not how you should do it unless your requirement is of resolving the traps in FM.

The design rockytopmark has mentioned is correct. The alias shortcut would be in the Database View. This alias shortcut will be referencing the original query subject but will have a different join startegy. You would then create a Model query subject in the Business View which will use the alias shortcut and finally  create a reference shortcut in the Presentation view.