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- 【TiDB 版本】：3.0.5
- 【问题描述】：
我们这边又分库合表使用dm同步mysql到tidb；
dm的配置中设置了：is-sharding: true
今天mysql增加了表的column；增加后发现dm同步任务中部分dm instance的同步报错了，提示如下：
{
“id”: 140,
“name”: “sharding table
futures_streamer.order_historyconsistency checking”, “desc”: “check consistency of sharding table structures”, “state”: “fail”, “errorMsg”: “column length mismatch (28 vs 31)\ tablefutures_streamer.order_history\ columns user_id bigint(20)\ order_id bigint(20)\ symbol varchar(10)\ account_id bigint(20)\ orig_client_order_id varchar(100)\ client_order_id varchar(100)\ price decimal(20,8)\ orig_qty decimal(20,8)\ executed_qty decimal(20,8)\ executed_quote_qty decimal(20,8)\ iceberg_qty decimal(20,8)\ status varchar(50)\ time_in_force varchar(10)\ type varchar(30)\ side varchar(10)\ stop_price decimal(20,8)\ target_strategy int(11)\ liquidation_cp_type tinyint(4)\ insert_time datetime\ create_update_id bigint(20)\ update_time datetime\ update_id bigint(20)\ order_list_id bigint(20)\ working_type tinyint(4)\ working_time bigint(20)\ working_indicator tinyint(1)\ db_create_time datetime(3)\ db_modify_time datetime(3)\ \ tablefutures_streamer.order_history\ columns user_id bigint(20)\ order_id bigint(20)\ symbol varchar(100)\ position_side tinyint(4)\ account_id bigint(20)\ orig_client_order_id varchar(100)\ client_order_id varchar(100)\ price decimal(20,8)\ orig_qty decimal(20,8)\ executed_qty decimal(20,8)\ executed_quote_qty decimal(20,8)\ iceberg_qty decimal(20,8)\ status varchar(50)\ time_in_force varchar(10)\ type varchar(30)\ side varchar(10)\ stop_price decimal(20,8)\ activate_price decimal(20,8)\ price_rate int(11)\ target_strategy int(11)\ liquidation_cp_type tinyint(4)\ insert_time datetime\ create_update_id bigint(20)\ update_time datetime\ update_id bigint(20)\ order_list_id bigint(20)\ working_type tinyint(4)\ working_time bigint(20)\ working_indicator tinyint(1)\ db_create_time datetime(3)\ db_modify_time datetime(3)\ ”,
登录到tidb发现mysql增加的column没有在tidb表中。 手动在tidb 执行 alter table add column后；重启dm task 发现启动不了了。报错：
{
"id": 140,
"name": "sharding table `futures_streamer`.`order_history` consistency checking",
"desc": "check consistency of sharding table structures",
"state": "fail",
"errorMsg": "column length mismatch (28 vs 31)\
table `futures_streamer`.`order_history`\
columns user_id bigint(20)\
order_id bigint(20)\
symbol varchar(10)\
account_id bigint(20)\
orig_client_order_id varchar(100)\
client_order_id varchar(100)\
price decimal(20,8)\
orig_qty decimal(20,8)\
executed_qty decimal(20,8)\
executed_quote_qty decimal(20,8)\
iceberg_qty decimal(20,8)\
status varchar(50)\
time_in_force varchar(10)\
type varchar(30)\
side varchar(10)\
stop_price decimal(20,8)\
target_strategy int(11)\
liquidation_cp_type tinyint(4)\
insert_time datetime\
create_update_id bigint(20)\
update_time datetime\
update_id bigint(20)\
order_list_id bigint(20)\
working_type tinyint(4)\
working_time bigint(20)\
working_indicator tinyint(1)\
db_create_time datetime(3)\
db_modify_time datetime(3)\
\
table`futures_streamer`.`order_history`\
columns user_id bigint(20)\
order_id bigint(20)\
symbol varchar(100)\
position_side tinyint(4)\
account_id bigint(20)\
orig_client_order_id varchar(100)\
client_order_id varchar(100)\
price decimal(20,8)\
orig_qty decimal(20,8)\
executed_qty decimal(20,8)\
executed_quote_qty decimal(20,8)\
iceberg_qty decimal(20,8)\
status varchar(50)\
time_in_force varchar(10)\
type varchar(30)\
side varchar(10)\
stop_price decimal(20,8)\
activate_price decimal(20,8)\
price_rate int(11)\
target_strategy int(11)\
liquidation_cp_type tinyint(4)\
insert_time datetime\
create_update_id bigint(20)\
update_time datetime\
update_id bigint(20)\
order_list_id bigint(20)\
working_type tinyint(4)\
working_time bigint(20)\
working_indicator tinyint(1)\
db_create_time datetime(3)\
db_modify_time datetime(3)\
",
"instruction": "please set same table structure for sharding tables",
"extra": "instance futures-streamer6 on sharding `futures_streamer`.`order_history`"
},
请问目前这种问题该如何处理？ 遇到类似的ddl问题，正确的处理过程应该是什么样的？万分感谢！！！
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