Twins are pretty rare. But we find they come in handy in our Anaplan modelling.

Twin lists or sometimes referred to as aliases or parallel lists are multiple individual lists which share a set of common properties and are therefore connected.

We have found that the most common uses for twin lists are the following;

Multiple parent hierarchies -

List item within a composite hierarchy can only have one parent. Where our clients want to summaries data up into cost centre for one report and manager in another we need the data to flow up and across more than one hierarchy and as a result we must use twin hierarchies to achieve this.

The focus here is to ensure that list items share a common code. This will ensure that mapping tables can be built and populated automatically as new items are added. We also need to ensure that new list items are added to all relevant twin lists at the same time to ensure data remains intact and maps effectively and accurately across all connected lists.

Combined list codes -

Often our clients want to model across a large number of dimensions. As a result it is difficult to avoid running in to sparsity challenges as the vast majority of the combined list items are not relevant but produce a vast number of active cells. The model resources used to calculate across these large number of cells is often unsustainable and inefficient.

We therefore we create combination lists to hold the data and manage model size. We achieve this by combining the codes of the relevant list items across all the dimension in active use to create one large master list.

However, list codes have a character limit of 60 where any code larger will be rejected. Where this presents a challenge instead of using the native lists we create and use a twin. These twin list items use a shorter code but crucially use the code of the original list as its name. When we code and map the combination list back to our original native list we can reference the name of our twin and pull through the original.