[GENERAL] Two entries with the same primary key

[Ivan Evtuhovich]

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)