--vacuum 之前
table_name | table_size | relfrozenxid | age
------------+------------+--------------+-----
users | 8192 bytes | 11361 | 95

vacuum verbose users;
--vacuum 之后
table_name | table_size | relfrozenxid | age
------------+------------+--------------+-----
users | 40 kB | 11361 | 95

表只有6条数据

(postgres@[local]:5432)-[testdb]-#select count(*) from users;
count
-------
6
(1 row)

(postgres@[local]:5432)-[testdb]-#\d users;
Table "public.users"
Column | Type | Collation | Nullable | Default
--------+-----------------------+-----------+----------+---------
id | integer | | |
name | character varying(30) | | |