pglogic中的replication set是逻辑复制中表的集合，默认自带了三个，如下：

logic=# select * from pglogical.replication_set;
   set_id   | set_nodeid |      set_name       | replicate_insert | replicate_update | replicate_delete | replicate_truncate 
------------+------------+---------------------+------------------+------------------+------------------+--------------------
 2551820615 | 2230476291 | default             | t                | t                | t                | t
  968332880 | 2230476291 | default_insert_only | t                | f                | f                | t
 3714372109 | 2230476291 | ddl_sql             | t                | f                | f                | f

在有多个订阅端的时候，可以利用replication set来标识表复制到那些订阅端。

发布端：

创建测试表

\c logic logic
logic=> create table tbl_test01 (a int primary key,b text);
logic=> insert  into tbl_test01 select t,t||'hank' from generate_series(1,100) as t;

创建replication set,并给set添加需要复制的表

\c logic postgres
logic=# select pglogical.create_replication_set('replica01');
 create_replication_set 
------------------------
             1500904000
logic=# select * from pglogical.replication_set;
   set_id   | set_nodeid |      set_name       | replicate_insert | replicate_update | replicate_delete | replicate_truncate 
------------+------------+---------------------+------------------+------------------+------------------+--------------------
 2551820615 | 2230476291 | default             | t                | t                | t                | t
  968332880 | 2230476291 | default_insert_only | t                | f                | f                | t
 3714372109 | 2230476291 | ddl_sql             | t                | f                | f                | f
 1500904000 | 2230476291 | replica01           | t                | t                | t                | t
logic=# select pglogical.replication_set_add_table('replica01','logic.tbl_test01');
 replication_set_add_table 
---------------------------
 t
(1 row)

logic=# select * from pglogical.tables ;
 relid | nspname |  relname   | set_name  
-------+---------+------------+-----------
 16653 | logic   | tbl_logic  | default
 16905 | logic   | tbl_test01 | replica01

订阅端：

创建subscription,加上replica01

logic=# select pglogical.create_subscription('sub_replica01', 'host=10.4.9.166 port=1921 user=postgres dbname=logic', ARRAY['replica01']);
 create_subscription 
---------------------
          1714075028


logic=# select count(*) from logic.tbl_test01 ;
 count 
-------
   100
(1 row)

给原有的subscription添加或删除replication set

#添加
logic=# select pglogical.alter_subscription_add_replication_set('logic_subscription','replica01' );
-[ RECORD 1 ]--------------------------+--
alter_subscription_add_replication_set | t

logic=# select * from pglogical.subscription;
-[ RECORD 1 ]-----------+------------------------------------------------
sub_id                  | 1714075028
sub_name                | sub_replica01
sub_origin              | 2230476291
sub_target              | 774206297
sub_origin_if           | 2529271354
sub_target_if           | 1665314130
sub_enabled             | t
sub_slot_name           | pgl_logic_logic_pub_sub_replica01
sub_replication_sets    | {replica01}
sub_forward_origins     | {all}
sub_apply_delay         | 00:00:00
sub_force_text_transfer | f
-[ RECORD 2 ]-----------+------------------------------------------------
sub_id                  | 218173469
sub_name                | logic_subscription
sub_origin              | 2230476291
sub_target              | 774206297
sub_origin_if           | 2529271354
sub_target_if           | 1665314130
sub_enabled             | t
sub_slot_name           | pgl_logic_logic_pub_logic_su0d01101
sub_replication_sets    | {default,default_insert_only,ddl_sql,replica01}
sub_forward_origins     | {all}
sub_apply_delay         | 00:00:00
sub_force_text_transfer | f

#删除
logic=# select pglogical.alter_subscription_remove_replication_set('logic_subscription','replica01' );
-[ RECORD 1 ]-----------------------------+--
alter_subscription_remove_replication_set | t

logic=# select * from pglogical.subscription;
-[ RECORD 1 ]-----------+--------------------------------------
sub_id                  | 1714075028
sub_name                | sub_replica01
sub_origin              | 2230476291
sub_target              | 774206297
sub_origin_if           | 2529271354
sub_target_if           | 1665314130
sub_enabled             | t
sub_slot_name           | pgl_logic_logic_pub_sub_replica01
sub_replication_sets    | {replica01}
sub_forward_origins     | {all}
sub_apply_delay         | 00:00:00
sub_force_text_transfer | f
-[ RECORD 2 ]-----------+--------------------------------------
sub_id                  | 218173469
sub_name                | logic_subscription
sub_origin              | 2230476291
sub_target              | 774206297
sub_origin_if           | 2529271354
sub_target_if           | 1665314130
sub_enabled             | t
sub_slot_name           | pgl_logic_logic_pub_logic_su0d01101
sub_replication_sets    | {default,default_insert_only,ddl_sql}
sub_forward_origins     | {all}
sub_apply_delay         | 00:00:00
sub_force_text_transfer | f

注意

如果上面添加replication set后，在订阅端又新创建了subscription，那么就会多出一个复制槽
logic=# select * from pg_replication_slots ;

pgl_logic_logic_pub_logic_su0d01101 | pglogical_output | logical   |  16651 | logic    | f         | t      |      16094 |      |          689 | 0/B7244600  | 0/B
7244638
pgl_logic_logic_pub_sub_replica01   | pglogical_output | logical   |  16651 | logic    | f         | t      |      22278 |      |          689 | 0/B7244600  | 0/B
7244638

如果是把replication set加入到原来的subscription,就还是用原来的复制槽
logic=# select * from pg_replication_slots ;
pgl_logic_logic_pub_logic_su0d01101 | pglogical_output | logical   |  16651 | logic    | f         | t      |      24520 |      |          701 | 0/B7265108  | 0/B
7265140

无论是新建subscription,还是添加到原来的subscription，复制表的效果是 一样的。