When a table is already used as the master table in one or more Relationships, the linkage between detail and master records is through the Key Field in the master table. Changing the Key Field without changes to the details tables would break these linkages.
Quick Base will modify the details tables as follows, in order to maintain the correct linkages:
A new reference field will be created in the details table. The value of this new reference field will be set in each record in the details table to the appropriate new key value from the master table in order to maintain the pre-existing linkage. If a lookup field to the new Key Field already exists in the details table, it will be converted to a non-lookup field and used as the new reference field.
All fields in the existing Relationship will be migrated to use the new reference field.
The new reference field will replace the old one on all forms in the details table.
The old reference field will be converted to a lookup field.