Two entries with the same primary key

[Ivan Evtuhovich <evtuhovich@xxxxxxxxx>]

Hello,

More then month ago we upgrade DB from 9.0 to 9.1 with pg_upgrade. Then we move DB to another server with standard pg streaming replication.

Now we have two entries with the same primary key. And I do not know what to do.

SELECT ctid, id from billing_invoices where id = 27362891;

     ctid     |    id    
--------------+----------
 (1112690,11) | 27362891
 (1112438,26) | 27362891

 \d billing_invoices
                                       Table "public.billing_invoices"
     Column     |            Type             |                           Modifiers                           

----------------+-----------------------------+---------------------------------------------------------------
 id             | integer                     | not null default nextval('billing_invoices_id_seq'::regclass)

...
 created_at     | timestamp without time zone | 
 updated_at     | timestamp without time zone | 
Indexes:
    "billing_invoices_pkey" PRIMARY KEY, btree (id)