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The level of validation is defined by the workflow and the data object from which the registration is created. If a registration is created for an order line which is serial number controlled, specific offline validation is enabled by default like only allowing one registration with the same value. This can of cause be overwritten, in those cases where that does not make sense. Specifically for the serial number that is done on the service level.
Controlling a specific barcode format can also be done through validators for order lines, utilizing the BarcodeFormat element.
Besides being controlled from the data object, specifics in the workflow can also affect validation, such as min/max value.
See Offline Validation validation for more information.
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