Change Events for Custom Field Type Conversions

When you change the type of a custom field, a change event or gap event is generated for data changes for some conversions. Other conversions, such as those that preserve or truncate field values, don’t generate events.

Conversions That Generate a Change Event

When converting a custom field type to another type that isn’t compatible, field data is lost and is set to null in records corresponding to the object. One change event is generated for all the affected records, and the event message contains no record fields.
Conversions That Generate a Gap Event

A gap event is generated for all the affected records for some field conversions from Picklist. The change event header of the gap event message contains information about the records, including the record IDs and a change type of GAP_UPDATE.
Conversions That Don’t Generate Events

No change or gap events are generated for custom field type conversions that preserve or truncate field data, and for conversions between Picklist and Text fields.

See Also