postgres=# create sequence seq;
CREATE SEQUENCE
postgres=# select * from seq;
 sequence_name | last_value | start_value | increment_by | max_value | min_value | cache_value | log_cnt | is_cycled | is_called | uuid 
---------------+------------+-------------+--------------+---------------------+-----------+-------------+---------+-----------+-----------+---------
 seq           | -1 | 1 | 1 | 9223372036854775807 | 1 | 1 | 0 | f         | f         | 1600007
(1 row)

postgres=# create sequence seq;
CREATE SEQUENCE
postgres=# insert into t_dest select nextval('seq'),* from t_src;
INSERT 0 0

postgres=# create table test(a int, b serial) distribute by hash(a);
NOTICE:  CREATE TABLE will create implicit sequence "test_b_seq" for serial column "test.b"
CREATE TABLE
postgres=#\d+ test
 Table "public.test"
 Column | Type |                    Modifiers                     | Storage | Stats target | Description 
--------+---------+--------------------------------------------------+---------+--------------+-------------
 a      | integer | | plain   | | 
 b      | integer | not null default nextval('test_b_seq'::regclass) | plain   | | 
Has OIDs: no
Distribute By: HASH(a)
Location Nodes: ALL DATANODES
Options: orientation=row, compression=no

postgres=# create table test(a int, b int) distribute by hash(a);
CREATE TABLE
postgres=# create sequence test_b_seq owned by test.b;
CREATE SEQUENCE
postgres=# alter sequence test_b_seq owner to jerry;  --jerry为test表的属主，如果当前用户即为属主，可不执行此语句
ALTER SEQUENCE
postgres=# alter table test alter b set default nextval('test_b_seq'), alter b set not null;
ALTER TABLE
postgres=# \d+ test
 Table "public.test"
 Column | Type |                    Modifiers                     | Storage | Stats target | Description 
--------+---------+--------------------------------------------------+---------+--------------+-------------
 a      | integer | | plain   | | 
 b      | integer | not null default nextval('test_b_seq'::regclass) | plain   | | 
Has OIDs: no
Distribute By: HASH(a)
Location Nodes: ALL DATANODES
Options: orientation=row, compression=no

postgres=# create table test1(a int, b serial) distribute by hash(a);
NOTICE:  CREATE TABLE will create implicit sequence "test1_b_seq" for serial column "test1.b"
CREATE TABLE
postgres=# 
postgres=# create table test2(a int) distribute by hash(a);
CREATE TABLE
postgres=# 
postgres=# 
postgres=# explain verbose insert into test1(a) select a from test2;
                                           QUERY PLAN 
------------------------------------------------------------------------------------------------
  id |             operation              | E-rows | E-distinct | E-memory | E-width | E-costs 
 ----+------------------------------------+--------+------------+----------+---------+---------
 1 | ->  Streaming (type: GATHER) | 1 | | | 4 | 18.41 
 2 | -> Insert on public.test1      | 40 | | | 4 | 18.25 
 3 | ->  Seq Scan on public.test2 | 40 | | 1MB      | 4 | 16.24 
 Targetlist Information (identified by plan id) 
 ---------------------------------------------------------
 1 --Streaming (type: GATHER)
         Node/s: All datanodes
 3 --Seq Scan on public.test2
         Output: test2.a, nextval('test1_b_seq'::regclass)
         Distribute Key: test2.a
 ====== Query Summary ===== 
 -------------------------------
 System available mem: 4669440KB
 Query Max mem: 4669440KB
 Query estimated mem: 1024KB
 Parser runtime: 0.045 ms
 Planner runtime: 12.622 ms
 Unique SQL Id: 972921662
(22 rows)

-- 解除当前sequence与目标表的关联关系
alter sequence test_b_seq owned by none;
alter table test alter b drop default;
-- 记录当前的seqeunce值并删除sequence
select nextval('test_b_seq'); --记录该值，作为新建sequence的start value
drop sequence test_b_seq;
-- 新建seqeunce并绑定目标表
create sequence test_b_seq START with xxx cache 10000 owned by t.b; -- xxx替换为上一步查到的nextval
alter sequence test_b_seq owner to jerry; --jerry为test表的属主，如果当前用户即为属主，可不执行此语句
alter table test alter b set default nextval('test_b_seq'), alter b set not null;