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There are different types of user fields
IdentifierFields (Mandatory): used to uniquely identify a user (i.e. OrgLoginId, login email address). Currently it supports one identifier field.
Critical field which needs data validation and would stop processing the whole user if it contained invalid data (skip user). Continue with any other users though.
Regular fields would not stop a user from being processed. If a regular field contained invalid data, the field would not be updated/set. The remaining user fields would be updated if their data was OK. Any not processed regular field should be reported on.
Password fields used for password creation only.
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