Logical replication behaves similarly to normal DML operations in that
   the data will be updated even if it was changed locally on the subscriber
   node.  If incoming data violates any constraints the replication will
   stop.  This is referred to as a conflict.  When
   replicating UPDATE or DELETE
   operations, missing data will not produce a conflict and such operations
   will simply be skipped.
  
A conflict will produce an error and will stop the replication; it must be resolved manually by the user. Details about the conflict can be found in the subscriber's server log.
   The resolution can be done either by changing data on the subscriber so
   that it does not conflict with the incoming change or by skipping the
   transaction that conflicts with the existing data.  The transaction can be
   skipped by calling the 
   pg_replication_origin_advance() function with
   a node_name corresponding to the subscription name,
   and a position.  The current position of origins can be seen in the
   
   pg_replication_origin_status system view.