Assignment always will be legal entity level; Assignment will always represent in your legal entity level.
Work Relationship tag in the enterprise level
Your assignment is your employment towards your own legal entity
Your work relationship is toward enterprise
Single Assignment - A and B legal entities - only one legal entity-relationship at a time
If an employee working in company A after some years he wants to switch to company B in the system GLOBAL TRANSFER option is used to switch between legal entities. In this situation A becomes inactive assignment and B becomes Active assignment.
Multiple Assignment - A and B legal entities - payroll from both, A and B both are active.
Single Contract Single Assignment - X is hired as a contractor in company A, X is hired permanent only in company A
Multiple Contract Single Assignment - X is hired as a contractor in companies A and B, and X is hired permanent into either A or B.
Work Relationship always will be Enterprise level
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