Thread: [BUG] pg_identify_object_as_address() returns duplicate values

Hi,

The documentation for this function says

"Returns a row containing enough information to uniquely identify the database object specified by catalog OID, object OID and sub-object ID"

However, this contract is broken for some pg_collation.oid values.

The problem is "collencoding" is not included in the data returned by pg_identify_object_as_address(),

but "collencoding" *is* included in the UNIQUE UNIQUE CONSTRAINT: (collname, collencoding, collnamespace).

Example:

SELECT pg_identify_object_as_address('pg_collation'::regclass,oid,0), * FROM pg_collation WHERE collname = 'en_GB';

    pg_identify_object_as_address    |  oid  | collname | collnamespace | collowner | collprovider | collisdeterministic | collencoding |   collcollate    |    collctype

-------------------------------------+-------+----------+---------------+-----------+--------------+---------------------+--------------+------------------+------------------

(collation,"{pg_catalog,en_GB}",{}) | 13662 | en_GB    |            11 |        10 | c            | t                   |            6 | en_GB            | en_GB

(collation,"{pg_catalog,en_GB}",{}) | 13754 | en_GB    |            11 |        10 | c            | t                   |            8 | en_GB.ISO8859-1  | en_GB.ISO8859-1

(collation,"{pg_catalog,en_GB}",{}) | 13755 | en_GB    |            11 |        10 | c            | t                   |           16 | en_GB.ISO8859-15 | en_GB.ISO8859-15

(3 rows)

/Joel