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Oracle: SQL statement to find primary-foreign key relations

By joining records of all_constraints that identify primary keys to records of all_constraints that identify foreign keys, it is possible to select primary-foreign key relations.
select
   pk.owner         pk_owner,
   pk.table_name    pk_table,
   fk.owner         fk_owner,
   fk.table_name    fk_table,  
   pk.status        pk_status,
   fk.status        fk_status
from
   all_constraints  pk                                                     join
   all_constraints  fk on pk.owner           = fk.r_owner            and
                          pk.constraint_name = fk.r_constraint_name
where
   pk.owner           =  user                 and
   pk.table_name      = 'XYZ' 
-- fk.constraint_name = 'ABC_FK'
;

See also

A variation of this SQL statement can be used to determine the involved parent and child table in case of an ORA-02291: integrity constraint … violated - parent key not found error message.
Error messages related to referential integrity.
referential integrity: foreign keys and primary keys.

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