-- view
CREATE TABLE t1(id int);
CREATE VIEW v1 AS SELECT * FROM t1;
DROP TABLE t1;
ERROR:  cannot drop table t1 because other objects depend on it
DETAIL:  view v1 depends on table t1
HINT:  Use DROP ... CASCADE to drop the dependent objects too.
DROP TABLE t1 CASCADE;
NOTICE:  drop cascades to view v1
\dt "trash".*
            List of relations
 Schema |    Name     | Type  |  Owner   
--------+-------------+-------+----------
 trash  | _3          | table | teledb
 trash  | trash_table | table | teledb
(2 rows)

\dv "trash".*
        List of relations
 Schema | Name | Type |  Owner   
--------+------+------+----------
 trash  | _3.1 | view | teledb
(1 row)

SELECT org_relname, new_relname, org_nspname, relowner FROM trash.trash_table;
 org_relname | new_relname | org_nspname | relowner 
-------------+-------------+-------------+----------
 test1       | _1          | public      | teledb
 test2       | _2          | public      | teledb
 t1          | _3          | public      | teledb
(3 rows)

-- matview
CREATE TABLE t2(id int);
CREATE MATERIALIZED VIEW mv1 AS SELECT * FROM t2;
DROP TABLE t2;
ERROR:  cannot drop table t2 because other objects depend on it
DETAIL:  materialized view mv1 depends on table t2
HINT:  Use DROP ... CASCADE to drop the dependent objects too.
DROP TABLE t2 CASCADE;
NOTICE:  drop cascades to materialized view mv1
\dt "trash".*
            List of relations
 Schema |    Name     | Type  |  Owner   
--------+-------------+-------+----------
 trash  | _3          | table | teledb
 trash  | _4          | table | teledb
 trash  | trash_table | table | teledb
(3 rows)

\dmv "trash".*
              List of relations
 Schema | Name |       Type        |  Owner   
--------+------+-------------------+----------
 trash  | _3.1 | view              | teledb
 trash  | _4.1 | materialized view | teledb
(2 rows)

SELECT org_relname, new_relname, org_nspname, relowner FROM trash.trash_table;
 org_relname | new_relname | org_nspname | relowner 
-------------+-------------+-------------+----------
 test1       | _1          | public      | teledb
 test2       | _2          | public      | teledb
 t1          | _3          | public      | teledb
 t2          | _4          | public      | teledb
(4 rows)

-- index
CREATE TABLE t3(id int);
CREATE INDEX i1 ON t3(id);
DROP TABLE t3;
\dt "trash".*
            List of relations
 Schema |    Name     | Type  |  Owner   
--------+-------------+-------+----------
 trash  | _3          | table | teledb
 trash  | _4          | table | teledb
 trash  | _5          | table | teledb
 trash  | trash_table | table | teledb
(4 rows)

\d+ "trash"._5
                                     Table "trash._5"
 Column |  Type   | Collation | Nullable | Default | Storage | Stats target | Description 
--------+---------+-----------+----------+---------+---------+--------------+-------------
 id     | integer |           | not null |         | plain   |              | 
Indexes:
    "_5.1" btree (id)
Distribute By: SHARD(id)
Location Nodes: ALL DATANODES

SELECT org_relname, new_relname, org_nspname, relowner FROM trash.trash_table;
 org_relname | new_relname | org_nspname | relowner 
-------------+-------------+-------------+----------
 test1       | _1          | public      | teledb
 test2       | _2          | public      | teledb
 t1          | _3          | public      | teledb
 t2          | _4          | public      | teledb
 t3          | _5          | public      | teledb
(5 rows)