sequence depends on many tables

[Mariel Cherkassky <mariel.cherkassky@xxxxxxxxx>]

Hey,

I'm handling a very weird situation. I tried to check which sequences belong to a specific table (table_A) with the following query : 

 WITH
sequences AS
(
SELECT oid,relname FROM pg_class WHERE relkind = 'S'
)
SELECT s.oid as seq_oid,d.objid as objid,d.refobjid
FROM pg_depend d,sequences s
where
s.oid = d.objid
and d.deptype = 'a'  and d.refobjid::regclass::text='table_A';
 seq_oid | objid | refobjid
---------+-------+----------
   17188 | 17188 |    17190
   16566 | 16566 |    17190
   16704 | 16704 |    17190
   16704 | 16704 |    17190
   16704 | 16704 |    17190
(5 rows)

17188 - The sequence of table_A(id)

16566 and 16704 are sequences that belong to different tables and arent used by table_A.

16566 - The sequence of table_c(id)

16704 - The sequence of tableB(id)

In all my environments I got exactly one rows (one seq owned by the id column (pk) of the table). In one specific environment I got a weird output(The one u see here). The output indicates that 2 other sequences  belongs to the current table when one of them have two rows that indicate it.

The next step was checking why it happened. I run the following query : 

select objid,refobjid::regclass from pg_depend where objid=16704;
 objid |        refobjid
-------+-------------------------
 16704 | 2200
 16704 | table_A
 16704 | table_A
 16704 | table_A
 16704 | table_B
(5 rows)

for unclear reason, both table A and table B depends on the sequence. When I check table_A I dont see any column that might use it..

I also checked who else depends on the 16556 objid : 

 select objid,refobjid::regclass from pg_depend where objid=16566;
 objid |       refobjid
-------+-----------------------
 16566 | 2200
 16566 | table_C
 16566 | table_A
 16566 | table_A_seq
(4 rows)

any idea how to handle this issue ? I checked this on both pg 9.6/12 versions and I got the same weird results.