What is a Multi-Active Satellite?
Multi-Active Satellites are used to store multiple entries per parent key; these records come from one denormalized data source.
They are useful to store an unknown number of similar records for the business key or transaction.
How to create a Multi-Active Satellite in 3D?
We will use the example of employees operating in multiple territories to describe the steps required to create a multi-active satellite.
Data Vault Design
This example incorporates data from 3 entities - Employee, EmployeeTerritories and Territories. Therefore, the query generates one row per Employee in each Territory (making the chosen Business Keys no longer unique).
- Ensure that the Satellite Multi Active key is also targeted as a Satellite Multi Active attribute.
- Without customization of the model conversion rules and attribute types, it is only possible to model one Multi Active Satellite per entity and source mapping set.
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Data Vault Model
Generate the Data Vault model using the workflow buttons in combination with the default model conversion rules.
- All of the extra DV control columns have been added to the entities as per DV 2.0 rules,
- Hub and Change hash keys have been added where needed.
- Naming standards have been applied as described when using the wizard. This includes a low rate of change (lroc) satellite and a multi active (ma) satellite.
- Data Types are only Logical at this stage.
Load and Staging Model
Generate the Load and Staging model using the workflow buttons in combination with the default model conversion rules.
- Load and Stage tables have now been generated.
- Load tables extract from the original mapped source.
- Stage tables introduce the hash columns. The Extended Properties of the hash keys in the Stage table identify on which column(s) the hash key is based.
- Trace the Table Source of the DV tables to see the modelling lineage.
- Some data types appear a bit strange (e.g. tgt_???). These will be resolved in the next model step.
Export to RED
Generate the RED Export model using the workflow buttons in combination with the default model conversion rules. Then after reviewing the model export it to WhereScape RED.