KingbaseES 分区表修改字段类型

KingbaseES普通表修改表结构请参考：KingbaseES变更表结构表重写问题

数据类型转换重写与不重写：

• varchar(x) 转换到 varchar(y) 当 y>=x，不需要重写。
• numeric(x,z) 转换到 numeric(y,z) 当 y>=x，或者不指定精度类型，不需要重写。
• numeric(x,c) 转换到 numeric(y,z) 当 y=x c>z，当numeric数据类型标度不一致时，需要重写。
• varbit(x) 转换到 varbit(y) 当 y>=x，不需要重写。
• timestamp(x) 转换到 timestamp(y) 当 y>=x，或者转换为timestamp，不需要重写。
• timestamptz(x) 转换到 timestamptz(y) 当 y>=x，或者转换为timestamptz，不需要重写。
• interval(x) 转换到 interval(y) 当 y>=x ，或者转换为interval，不需要重写。
• timestamp 转换到 text、varchar、varchar(n)，char(n)，需要重写。
• timestamp(x)转换到 text、varchar、varchar(n)、char(n)，n>=x，需要重写。
• text 转换到 char、char(x)、varchar(n)，需要重写。
• text 转换到 varchar，不需要重写。
• numeric(x) 转换到 numeric(y)，y>=x，不需要重写。
• numeric(x) 转换到 numeric，不需要重写。
• numeric(x,y) 转换到 numeric，不需要重写。

一、普通表的修改：

普通表数据类型长度或者精度由小改大表不会重写，索引也不会重写。

test=# create table t01(id int,name varchar(10));
CREATE TABLE
test=# insert into t01 select generate_series(1,10),substr(md5(random()::text),1,10);
INSERT 0 10
test=# create index on t01 (name);
CREATE INDEX
test=# \d t01
                          Table "public.t01"
 Column |            Type            | Collation | Nullable | Default 
--------+----------------------------+-----------+----------+---------
 id     | integer                    |           |          | 
 name   | character varying(10 char) |           |          | 
Indexes:
    "t01_name_idx" btree (name)

test=# 
test=# select sys_relation_filenode('t01'),sys_relation_filenode('t01_name_idx');
 SYS_RELATION_FILENODE | SYS_RELATION_FILENODE 
-----------------------+-----------------------
                289043 |                289046
(1 row)

# 设置客户端消息级别client_min_messages=debug5
test=# set client_min_messages=debug5;

# 修改t01表name字段长度varchar(10)为varchar(15)
test=# alter table t01 alter column name type varchar(15);
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  EventTriggerInvoke 267860
DEBUG:  rehashing catalog cache id 68 for sys_recyclebin; 33 tups, 16 buckets
DEBUG:  EventTriggerInvoke 13761
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 428092/1/7
ALTER TABLE

test=# select sys_relation_filenode('t01'),sys_relation_filenode('t01_name_idx');
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
 SYS_RELATION_FILENODE | SYS_RELATION_FILENODE 
-----------------------+-----------------------
                289043 |                289046
(1 row)

test=# 

分区表修改表结构是否跟普通表一样？

二、分区表的修改：

分区表分区键无法修改数据类型，本测试只针对非分区键进行测试。

create table tb(id bigint,pdate date,info varchar2(10)) partition by range(pdate) INTERVAL ('1 MONTH'::INTERVAL)
(
PARTITION tb_p0 VALUES LESS THAN ('2023-01-01'),
PARTITION tb_p1 VALUES LESS THAN ('2023-02-01'),
PARTITION tb_p2 VALUES LESS THAN ('2023-03-01'),
PARTITION tb_p3 VALUES LESS THAN ('2023-04-01')
);
CREATE TABLE
insert into tb select generate_series(1,100),'2023-01-01'::date,substr(md5(random()::text),1,10);
INSERT 0 100
insert into tb select generate_series(101,200),'2023-02-01'::date,substr(md5(random()::text),1,10);
INSERT 0 100
insert into tb select generate_series(201,300),'2023-03-01'::date,substr(md5(random()::text),1,10);
INSERT 0 100

2.1.分区表非索引列数据类型的修改：

修改非索引列的类型：由小改大，表不会发生重写，索引自然也没有发生重写。

修改非索引列的类型：由大改小，遵循KingbaseES变更表结构表重写规则，表需要重写，索引也需要重写。

test=# set client_min_messages =debug5;
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
SET
test=# select oid,relname from sys_class where relname='tb';      
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
  OID   | RELNAME 
--------+---------
 289063 | tb
(1 row)

test=# select oid,relname from sys_class where relname='tb_tb_p0';
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
  OID   | RELNAME  
--------+----------
 289066 | tb_tb_p0
(1 row)

test=# select oid,relname from sys_class where relname='tb_tb_p1';
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
  OID   | RELNAME  
--------+----------
 289069 | tb_tb_p1
(1 row)

test=# select oid,relname from sys_class where relname='tb_tb_p2';
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
  OID   | RELNAME  
--------+----------
 289072 | tb_tb_p2
(1 row)

test=# select oid,relname from sys_class where relname='tb_tb_p3';
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
  OID   | RELNAME  
--------+----------
 289075 | tb_tb_p3
(1 row)

# 修改tb分区表info列为varchar(20)
test=# alter table tb alter column info type varchar(20);
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  EventTriggerInvoke 267860
DEBUG:  EventTriggerInvoke 13761
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 428111/1/10
ALTER TABLE

test=# select oid,relname from sys_class where relname='tb';      
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
  OID   | RELNAME 
--------+---------
 289063 | tb
(1 row)

test=# select oid,relname from sys_class where relname='tb_tb_p0';
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
  OID   | RELNAME  
--------+----------
 289066 | tb_tb_p0
(1 row)

test=# select oid,relname from sys_class where relname='tb_tb_p1';
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
  OID   | RELNAME  
--------+----------
 289069 | tb_tb_p1
(1 row)

test=# select oid,relname from sys_class where relname='tb_tb_p2';
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
  OID   | RELNAME  
--------+----------
 289072 | tb_tb_p2
(1 row)

test=# select oid,relname from sys_class where relname='tb_tb_p3';
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
  OID   | RELNAME  
--------+----------
 289075 | tb_tb_p3
(1 row)

test=# alter table tb alter column info type varchar(30);                 
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  EventTriggerInvoke 267860
DEBUG:  EventTriggerInvoke 13761
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 428112/1/10
ALTER TABLE
test=# select oid,relname from sys_class where relname='tb';      
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
  OID   | RELNAME 
--------+---------
 289063 | tb
(1 row)

test=# select oid,relname from sys_class where relname='tb_tb_p0';
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
  OID   | RELNAME  
--------+----------
 289066 | tb_tb_p0
(1 row)

test=# select oid,relname from sys_class where relname='tb_tb_p1';
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
  OID   | RELNAME  
--------+----------
 289069 | tb_tb_p1
(1 row)

test=# select oid,relname from sys_class where relname='tb_tb_p2';
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
  OID   | RELNAME  
--------+----------
 289072 | tb_tb_p2
(1 row)

test=# select oid,relname from sys_class where relname='tb_tb_p3';
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
  OID   | RELNAME  
--------+----------
 289075 | tb_tb_p3
(1 row)

分区表修改非索引列字段长度或者是精度由小变大，跟普通表一样，不需要重写。

2.2.分区表全局（GLOBAL）索引列数据类型的修改：

修改全局（GLOBAL）索引列的类型：由小改大，表不会发生重写，索引也没有发生重写。

修改全局（GLOBAL）索引列的类型：由大改小，遵循KingbaseES变更表结构表重写规则，表需要重写，索引也需要重写。

test=# \d+ tb                          
                                        Partitioned table "public.tb"
 Column |            Type            | Collation | Nullable | Default | Storage  | Stats target | Description 
--------+----------------------------+-----------+----------+---------+----------+--------------+-------------
 id     | bigint                     |           |          |         | plain    |              | 
 pdate  | date                       |           |          |         | plain    |              | 
 info   | character varying(10 char) |           | not null |         | extended |              | 
Partition key: RANGE (pdate)
Range interval: INTERVAL ('0-1'::pg_catalog.interval)
Partitions: tb_tb_p0 FOR VALUES FROM (MINVALUE) TO ('2023-01-01 00:00:00'),
            tb_tb_p1 FOR VALUES FROM ('2023-01-01 00:00:00') TO ('2023-02-01 00:00:00'),
            tb_tb_p2 FOR VALUES FROM ('2023-02-01 00:00:00') TO ('2023-03-01 00:00:00'),
            tb_tb_p3 FOR VALUES FROM ('2023-03-01 00:00:00') TO ('2023-04-01 00:00:00')

# 添加主键
test=# alter table tb add constraint tb_pk primary key (info);
ALTER TABLE
test=# \d+ tb
                                        Partitioned table "public.tb"
 Column |            Type            | Collation | Nullable | Default | Storage  | Stats target | Description 
--------+----------------------------+-----------+----------+---------+----------+--------------+-------------
 id     | bigint                     |           |          |         | plain    |              | 
 pdate  | date                       |           |          |         | plain    |              | 
 info   | character varying(10 char) |           | not null |         | extended |              | 
Partition key: RANGE (pdate)
Range interval: INTERVAL ('0-1'::pg_catalog.interval)
Indexes:
    "tb_pk" PRIMARY KEY, btree (info) INCLUDE (tableoid) GLOBAL 
Partitions: tb_tb_p0 FOR VALUES FROM (MINVALUE) TO ('2023-01-01 00:00:00'),
            tb_tb_p1 FOR VALUES FROM ('2023-01-01 00:00:00') TO ('2023-02-01 00:00:00'),
            tb_tb_p2 FOR VALUES FROM ('2023-02-01 00:00:00') TO ('2023-03-01 00:00:00'),
            tb_tb_p3 FOR VALUES FROM ('2023-03-01 00:00:00') TO ('2023-04-01 00:00:00')

test=# select sys_relation_filepath('tb_pk');                     
 SYS_RELATION_FILEPATH 
-----------------------
 base/12176/289111
(1 row)

test=# select oid,relname from sys_class where relname='tb';      
  OID   | RELNAME 
--------+---------
 289063 | tb
(1 row)

test=# select oid,relname from sys_class where relname='tb_tb_p0';
  OID   | RELNAME  
--------+----------
 289066 | tb_tb_p0
(1 row)

test=# select oid,relname from sys_class where relname='tb_tb_p1';
  OID   | RELNAME  
--------+----------
 289069 | tb_tb_p1
(1 row)

test=# select oid,relname from sys_class where relname='tb_tb_p2';
  OID   | RELNAME  
--------+----------
 289072 | tb_tb_p2
(1 row)

test=# select oid,relname from sys_class where relname='tb_tb_p3';
  OID   | RELNAME  
--------+----------
 289075 | tb_tb_p3
(1 row)

test=# alter table tb alter info type varchar(20);
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  EventTriggerInvoke 267860
DEBUG:  drop auto-cascades to index tb_pk
DEBUG:  EventTriggerInvoke 13761
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 428121/1/19
ALTER TABLE
test=# select sys_relation_filepath('tb_pk');                     
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
 SYS_RELATION_FILEPATH 
-----------------------
 base/12176/289111
(1 row)

test=# select oid,relname from sys_class where relname='tb';      
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
  OID   | RELNAME 
--------+---------
 289063 | tb
(1 row)

test=# select oid,relname from sys_class where relname='tb_tb_p2';
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
  OID   | RELNAME  
--------+----------
 289072 | tb_tb_p2
(1 row)

# 添加全局索引
test=# create unique index on tb(id,info) global;
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  EventTriggerInvoke 267860
DEBUG:  building index "tb_id_info_idx" on table "tb" serially
DEBUG:  EventTriggerInvoke 13761
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 428122/1/4
CREATE INDEX
test=# \d+ tb
                                        Partitioned table "public.tb"
 Column |            Type            | Collation | Nullable | Default | Storage  | Stats target | Description 
--------+----------------------------+-----------+----------+---------+----------+--------------+-------------
 id     | bigint                     |           |          |         | plain    |              | 
 pdate  | date                       |           |          |         | plain    |              | 
 info   | character varying(20 char) |           | not null |         | extended |              | 
Partition key: RANGE (pdate)
Range interval: INTERVAL ('0-1'::pg_catalog.interval)
Indexes:
    "tb_pk" PRIMARY KEY, btree (info) INCLUDE (tableoid) GLOBAL 
    "tb_id_info_idx" UNIQUE, btree (id, info) INCLUDE (tableoid) GLOBAL 
Partitions: tb_tb_p0 FOR VALUES FROM (MINVALUE) TO ('2023-01-01 00:00:00'),
            tb_tb_p1 FOR VALUES FROM ('2023-01-01 00:00:00') TO ('2023-02-01 00:00:00'),
            tb_tb_p2 FOR VALUES FROM ('2023-02-01 00:00:00') TO ('2023-03-01 00:00:00'),
            tb_tb_p3 FOR VALUES FROM ('2023-03-01 00:00:00') TO ('2023-04-01 00:00:00')

test=# select sys_relation_filepath('tb_pk');                     
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
 SYS_RELATION_FILEPATH 
-----------------------
 base/12176/289111
(1 row)

test=# select sys_relation_filepath('tb_id_info_idx');
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
 SYS_RELATION_FILEPATH 
-----------------------
 base/12176/289115
(1 row)

test=# alter table tb alter info type varchar(30);
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  EventTriggerInvoke 267860
DEBUG:  drop auto-cascades to index tb_pk
DEBUG:  EventTriggerInvoke 13761
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 428123/1/27
ALTER TABLE
test=# select sys_relation_filepath('tb_pk');                     
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
 SYS_RELATION_FILEPATH 
-----------------------
 base/12176/289111
(1 row)

test=# select sys_relation_filepath('tb_id_info_idx');
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
 SYS_RELATION_FILEPATH 
-----------------------
 base/12176/289115
(1 row)

分区表修改全局（GLOBAL）索引列字段长度或者是精度由小变大，跟普通表一样，不需要重写。

2.3.分区表本地（LOCAL）索引列数据类型的修改：

修改本地（LOCAL）索引列的类型：由小改大，表不会发生重写，索引发生重写。

修改本地（LOCAL）索引列的类型：由大改小，遵循KingbaseES变更表结构表重写规则，表需要重写，索引也需要重写。

test=# \d+ tb
                                        Partitioned table "public.tb"
 Column |            Type            | Collation | Nullable | Default | Storage  | Stats target | Description 
--------+----------------------------+-----------+----------+---------+----------+--------------+-------------
 id     | bigint                     |           |          |         | plain    |              | 
 pdate  | date                       |           |          |         | plain    |              | 
 info   | character varying(30 char) |           | not null |         | extended |              | 
Partition key: RANGE (pdate)
Range interval: INTERVAL ('0-1'::pg_catalog.interval)
Indexes:
    "tb_pk" PRIMARY KEY, btree (info) INCLUDE (tableoid) GLOBAL 
    "tb_id_info_idx" UNIQUE, btree (id, info) INCLUDE (tableoid) GLOBAL 
Partitions: tb_tb_p0 FOR VALUES FROM (MINVALUE) TO ('2023-01-01 00:00:00'),
            tb_tb_p1 FOR VALUES FROM ('2023-01-01 00:00:00') TO ('2023-02-01 00:00:00'),
            tb_tb_p2 FOR VALUES FROM ('2023-02-01 00:00:00') TO ('2023-03-01 00:00:00'),
            tb_tb_p3 FOR VALUES FROM ('2023-03-01 00:00:00') TO ('2023-04-01 00:00:00')

# 创建本地索引
test=# create index on tb(pdate,info);        
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  EventTriggerInvoke 267860
DEBUG:  building index "tb_tb_p0_pdate_info_idx" on table "tb_tb_p0" serially
DEBUG:  building index "tb_tb_p1_pdate_info_idx" on table "tb_tb_p1" serially
DEBUG:  building index "tb_tb_p2_pdate_info_idx" on table "tb_tb_p2" serially
DEBUG:  building index "tb_tb_p3_pdate_info_idx" on table "tb_tb_p3" serially
DEBUG:  EventTriggerInvoke 13761
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 428125/1/12
CREATE INDEX
test=# \d+ tb
                                        Partitioned table "public.tb"
 Column |            Type            | Collation | Nullable | Default | Storage  | Stats target | Description 
--------+----------------------------+-----------+----------+---------+----------+--------------+-------------
 id     | bigint                     |           |          |         | plain    |              | 
 pdate  | date                       |           |          |         | plain    |              | 
 info   | character varying(30 char) |           | not null |         | extended |              | 
Partition key: RANGE (pdate)
Range interval: INTERVAL ('0-1'::pg_catalog.interval)
Indexes:
    "tb_pk" PRIMARY KEY, btree (info) INCLUDE (tableoid) GLOBAL 
    "tb_id_info_idx" UNIQUE, btree (id, info) INCLUDE (tableoid) GLOBAL 
    "tb_pdate_info_idx" btree (pdate, info)
Partitions: tb_tb_p0 FOR VALUES FROM (MINVALUE) TO ('2023-01-01 00:00:00'),
            tb_tb_p1 FOR VALUES FROM ('2023-01-01 00:00:00') TO ('2023-02-01 00:00:00'),
            tb_tb_p2 FOR VALUES FROM ('2023-02-01 00:00:00') TO ('2023-03-01 00:00:00'),
            tb_tb_p3 FOR VALUES FROM ('2023-03-01 00:00:00') TO ('2023-04-01 00:00:00')


test=# select sys_relation_filepath('tb_pk'),sys_relation_filepath('tb_id_info_idx');
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
 SYS_RELATION_FILEPATH | SYS_RELATION_FILEPATH 
-----------------------+-----------------------
 base/12176/289111     | base/12176/289115
(1 row)

test=# select oid,relname from sys_class where relname='tb_pdate_info_idx';
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
  OID   |      RELNAME      
--------+-------------------
 289119 | tb_pdate_info_idx
(1 row)

# 修改本地索引依赖info列
test=# alter table tb alter info type varchar(40);
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  EventTriggerInvoke 267860
DEBUG:  drop auto-cascades to index tb_tb_p0_pdate_info_idx
DEBUG:  drop auto-cascades to index tb_tb_p1_pdate_info_idx
DEBUG:  drop auto-cascades to index tb_tb_p2_pdate_info_idx
DEBUG:  rehashing catalog cache id 68 for sys_recyclebin; 33 tups, 16 buckets
DEBUG:  drop auto-cascades to index tb_tb_p3_pdate_info_idx
DEBUG:  drop auto-cascades to index tb_pk
DEBUG:  building index "tb_tb_p0_pdate_info_idx" on table "tb_tb_p0" serially
DEBUG:  building index "tb_tb_p1_pdate_info_idx" on table "tb_tb_p1" serially
DEBUG:  building index "tb_tb_p2_pdate_info_idx" on table "tb_tb_p2" serially
DEBUG:  building index "tb_tb_p3_pdate_info_idx" on table "tb_tb_p3" serially
DEBUG:  EventTriggerInvoke 13761
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 428127/1/51
ALTER TABLE
test=# select sys_relation_filepath('tb_pk'),sys_relation_filepath('tb_id_info_idx');
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
 SYS_RELATION_FILEPATH | SYS_RELATION_FILEPATH 
-----------------------+-----------------------
 base/12176/289111     | base/12176/289115
(1 row)

test=# select oid,relname from sys_class where relname='tb_pdate_info_idx';          
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state: INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state: INPROGRESS, xid/subid/cid: 0/1/0
  OID   |      RELNAME      
--------+-------------------
 289127 | tb_pdate_info_idx
(1 row)

test=# 

分区表本地（LOCAL）索引列修改字段长度或者是精度由小变大，表、全局索引不需要重写，但是本地索引需要重写。

2.4.分区表修改表结构总结：

• 分区表修改非索引列字段长度或者是精度由小变大，跟普通表一样，不需要重写。

• 分区表修改全局（GLOBAL）索引列字段长度或者是精度由小变大，跟普通表一样，不需要重写。

• 分区表本地（LOCAL）索引列修改字段长度或者是精度由小变大，表、全局索引不需要重写，但是本地索引需要重写。

三、分区表变更表结构的思考：

通过以上测试可知：分区表修改本地索引依赖字段长度或者标度会导致索引重写。

如果分区表数据量大、子分区多、字段列依赖的索引多，修改分区表（本地索引）列字段长度会发生如下问题：

修改字段长度由小到大：分区表所有的子表不会发生重写，但是索引会发生重写，索引越多阻塞时间越长。

目前想到的解决方法：删除被修改列依赖的所有本地索引，避免长时间的AccessExclusiveLock，修改完成后子表使用concurrently的方式创建。

修改字段长度由大到小：分区表所有的子表都会发生重写，只要表发生重写所有的索引都需要重写，此过程会导致业务不可用（影响太大）。

对分区表使用detach？分区表要求所有子分区的表结构必须跟父表一致，所有的子分区全部修改完成后再attach回去，跟直接改区别不大，可以避免业务中断。需要根据业务提前准备好脚本。

本栏目推荐文章
• 函数的参数类型
• 引用数据类型
• 11-函数进阶-参数类型
• 2024-01-13：用go语言，现在有一个打怪类型的游戏，这个游戏是这样的，你有n个技能， 每一个技能会有一个伤害， 同时若怪物小于等于一定的血量，则该技能可能造成双倍伤害， 每一个技能最多只能释放
• 春眠不觉晓，Java数据类型知多少？基础牢不牢看完本文就有数了
• Chrome 浏览器插件 V3 版本 Manifest.json 文件中 Action 的类型（Types）、方法（Methods）和事件（Events）的属性和参数解析
• go语言多态中的类型断言
• 用友 U9 【料品表】全字段Sql输出
• 面试题：Java中的引用类型有哪几种？特点是什么？
• 模型层choice字段使用

字段 KingbaseES 类型字段kingbasees类型 kingbasees类型 二进制kingbasees类型 数据 字段sqlserver类型 数据 字段 索引 类型 字段keyword类型query 字段timestamp类型oracle 字段sqlite3类型sqlite 字段mysql-json类型mysql 布尔 字段 报表 类型