Create a Non-Historized Link Satellite

A Model Object of type Non-Historized Link Satellite can be created in the Silver Layer.

What is a Non-Historized Link Satellite

In a Data Vault model, a Non-Historized Link Satellite, also known as a No-History Link or Transactional Link, permits the avoidance of the check of data existence so it is more performant.

It can be used when source data is only loaded once or is never updated as transactional data.

Creation steps

There are two possibilities to create a Non-Historized Link Satellite Model Object:

• Create a Model Object with the Wizard:
  • Recommended possibility
  • Use the Wizard Create a Non-Historized Link Satellite from a Stage or a Stage Composite that contains the following steps:
    • Create Model Object
    • Create Dataflow
    • Create Relations: number = {1}
    • Map Foreign Key Terms
    • Map selected Terms: exclude the Business Key(s) = {true}, exclude the Foreign Key(s) = {true}
    • Add to View
• Create a Model Object manually:
  • Not recommended possibility
  • Create a Model Object of type Non-Historized Link Satellite in the Silver Layer
  • Create a Dataflow Set 
  • Add a Model Object to the Dataflow Set: Add the Stage Model Object
  • Auto-map the Source Terms: Select the auto-map mode and auto-map all the Source Terms except the ones defined as Business Keys and the Default Source Terms in the Source Model Object
  • Add a Relationship to the corresponding Link
  • Map the Foreign Key Terms: Select the target mode and manually map the Foreign Key Terms to the corresponding Source Terms (with or without a complex expression)

Properties

A Non-Historized Link Satellite Model Object can be configured through the following Properties: 

• Implementation Type

• Deduplication Method or Optimization Method (Only for Spark Generator)

• Deduplication Partition or Optimization Method Columns (Only for Spark Generator)
• File format (Only for Spark Generator)

Default Terms

A Non-Historized Link Satellite Model Object will include the following Default Terms:  

• BG_LoadTimestamp

• Link_HK

• BG_SourceSystem

Business Rules

The following Business Rules are checked during the Model Object creation:

• Dataflows amount: min = {1}, max = {null}
• Dataflow Sets amount: min = {1}, max = {null}
• Dataflow Set Model Objects amount: min = {1}, max = {null}
• Relationships amount: min = {1}, max = {1}
• Supported Term Data Types: exclude Default Terms = {true}, exclude Business Keys = {false}, exclude Identities = {false}, exclude Foreign Keys = {false}, exclude unmapped Terms = {false}
• Business Key Terms amount: min = {null}, max = {0}
• Identity Terms amount: min = {1}, max = {1}
• Identity Terms not nullable
• Supported Implementation Types: supported Implementation Types = {Permanent}
• Supported Deduplication Methods: supported deduplication Methods = {None, Distinct, Partition}
• Supported Load Cachings: supported Load Cachings = {Hashing}
• Foreign Key Mapping