Hi
It depends on what items on the assignment you are migrating
update_emp_asg_criteria is used to update anything on the assignment that could control eligibility for an element - e.g. grade, job, position, people group, payroll etc
update_emp_asg (or for UK legislation you can - and should - use update_gb_emp_asg) will do the other things such as supervisor, normal hours, assignment desc flex etc.
For any given assignment record, it is more than likely you will need to call both of these apis to furnish all the required data.
activate_emp_asg is more of a process than a simple 'update', as it controls the switching of the assignment status ONLY - specifically, to some flavour of 'ACTIVE_ASSIGN'. In a migration context it is unlikely (but not impossible) that you would need to make use of it. The default employee assignment has its assignment status set to the default flavour of ACTIVE_ASSIGN (which may well be 'Active Assignment') at creation time.
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L&K
CT
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