parition table can not change decimal type

[lizhenhuan]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

create table :

CREATE TABLE `cis_assay_report_detail` (
  `org_code` varchar(9) NOT NULL ,
  `branch_code` varchar(2) NOT NULL DEFAULT '00' ,
  `report_no` varchar(20) NOT NULL ,
  `report_seqno` varchar(22) NOT NULL ,
  `report_seq` varchar(22) NOT NULL ,
  `reg_id` varchar(22) DEFAULT NULL ,
  report_time datetime,
  `modify_empid` varchar(10) DEFAULT NULL ,
  `modify_empid_code_org` varchar(64) DEFAULT NULL ,
  `modify_empid_name_org` varchar(256) DEFAULT NULL ,
  `create_time_sys` timestamp(6) DEFAULT CURRENT_TIMESTAMP(6) ,
  `create_empid` varchar(10) DEFAULT NULL ,
  `create_empid_code_org` varchar(64) DEFAULT NULL ,
  `create_empid_name_org` varchar(256) DEFAULT NULL ,
  `modify_time_mfs` datetime DEFAULT NULL ,
  `create_time_mfs` datetime DEFAULT NULL ,
  `batch_version` varchar(40) DEFAULT NULL ,
  `batch_type` varchar(10) DEFAULT NULL ,
  `time_correlation_mark` varchar(2) NOT NULL DEFAULT '0' ,
  `modify_time_center` timestamp(6) DEFAULT CURRENT_TIMESTAMP(6) ON UPDATE CURRENT_TIMESTAMP(6) ,
  `create_time_center` timestamp(6) DEFAULT CURRENT_TIMESTAMP(6) ,
  PRIMARY KEY (`report_time`,`org_code`,`branch_code`,`report_no`,`report_seqno`,`report_seq`) /*T![clustered_index] NONCLUSTERED */
  
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin 
PARTITION BY RANGE COLUMNS(`report_time`)
(PARTITION `p201001` VALUES LESS THAN ('2010-02-01 00:00:00'),
 PARTITION `p201002` VALUES LESS THAN ('2010-03-01 00:00:00'),
 PARTITION `p201003` VALUES LESS THAN ('2010-04-01 00:00:00'),
 PARTITION `p201004` VALUES LESS THAN ('2010-05-01 00:00:00'),
 PARTITION `p201005` VALUES LESS THAN ('2010-06-01 00:00:00'),
 PARTITION `pmax` VALUES LESS THAN (MAXVALUE))

alter table cis_assay_report_detail change column limit_lower limit_lower varchar(64);
Query OK, 0 rows affected (0.06 sec)

mysql> alter table cis_assay_report_detail add column test_decimal decimal(9,2);
Query OK, 0 rows affected (0.17 sec)

mysql> alter table cis_assay_report_detail change column test_decimal test_decimal decimal(11,2);
ERROR 8200 (HY000): Unsupported modify column: table is partition table

It works on normal table

create table t (test_decimal decimal(9,2));
Query OK, 0 rows affected (0.05 sec)

mysql> alter table t change column test_decimal test_decimal decimal(11,2);
Query OK, 0 rows affected (0.19 sec)

2. What did you expect to see? (Required)

alter table cis_assay_report_detail change column test_decimal test_decimal decimal(11,2);
execute success

3. What did you see instead (Required)

alter table cis_assay_report_detail change column test_decimal test_decimal decimal(11,2);
ERROR 8200 (HY000): Unsupported modify column: table is partition table

4. What is your TiDB version? (Required)

tidb 8.4

[mjonss]

Related to #38297, should be fixed by #40634.