'Tests that changing primary key implicitly fails.'

def test_primary_key_implicit(self):

    db.create_table('test_pki', [('id', models.IntegerField(primary_key=True)), ('new_pkey', models.IntegerField()), ('eggs', models.IntegerField(unique=True))])
    db.execute_deferred_sql()
    db.alter_column('test_pki', 'id', models.IntegerField())
    db.alter_column('test_pki', 'new_pkey', models.IntegerField(primary_key=True))
    db.execute('INSERT    INTO    test_pki    (id,    new_pkey,    eggs)    VALUES    (1,    2,    3)')
    db.execute('INSERT    INTO    test_pki    (id,    new_pkey,    eggs)    VALUES    (2,    2,    4)')
    db.delete_table('test_pki')
