In this scenario the artefact in the core folder has been replaced with the upgraded artefact and the customer wants to take on these upgrade changes. However, the customer has already made changes to the artefact which is in the custom folder. The customer must manually make the upgraded changes to the customized artefact. To do this the customer must check for differences in the new upgraded artefact (a comparison utility may be helpful to compare certain artifacts) and adopt these upgrade changes into the customized artefact.
An example of this is a change to the DW_ADDRESS_ETL meta data. There has been an upgrade to this ETL to include a new destination field. However the customer has already modified the meta data by deleting an existing column which they do not need. To adopt the upgrade the customer must check for the differences with the new upgraded artefact to find the new destination column. The customer can then modify their customized ETL in the custom folder to add this destination field. The build script will always take this meta data in the custom folder before the core folder.