Business Key
The business key is the column or columns that uniquely identify a record within a Data Store Object. Where the Data Store Object maps back to a single or a main table in the source system, it is usually possible to ascertain the business key by looking at the unique keys for that source table. The business key is sometimes referred to as the 'natural' key. Examples of business keys are:
The product SKU in a product table
The customer code in a customer table
The IATA airport code in an airport table.
It is assumed that business keys will never be NULL. If a null value is possible in a business key then the generated code will need to be modified to handle the null value by assigning some default value. In the following examples, the business key column is modified by using a database function and default value:
DB2: COALESCE(business_key,'N/A')
SQL Server: ISNULL(business_key,'N/A')
Oracle: NVL(business_key,'N/A')
Note: Business keys are assumed to never be Null. If they can be null it is best to transform them to some value prior to the Data Store or stage table update. If this is not done, an un-modified update procedure will probably fail with a duplicate key error on the business key index.
Building a Data Store Object
Data Store Objects are often sourced from one table in the base application. The process for building a Data Store Object begins with the drag and drop of the load or stage table that contains the bulk of the Data Store Object's information.