I create a empty table and then alter this table's "AUTO_INCREMENT" starts from 10000000.After a long time ,MySQL lost "AUTO_INCREMENT" definition when I show this table again. MariaDB has the same problem but Percona Server is fine.

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mysql> use test;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> DROP TABLE IF EXISTS `test_bug` ;
Query OK, 0 rows affected, 1 warning (0.00 sec)


mysql> CREATE TABLE test_bug (
    ->   `id` BIGINT PRIMARY KEY NOT NULL AUTO_INCREMENT,
    ->   `consult_order_id` BIGINT ,
    ->   `pay_channel` INT COMMENT ,
    ->   `price` BIGINT ,
    ->   `trade_no` VARCHAR (64) ,
    ->   `right_no` VARCHAR (64) ,
    ->   `item_id` BIGINT NOT NULL,
    ->   `source_type` INT NOT NULL ,
    ->   `gmt_create` DATETIME DEFAULT CURRENT_TIMESTAMP ,
    ->   `gmt_modified` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP 
    -> ) ENGINE = INNODB DEFAULT CHARSET = utf8 ;
Query OK, 0 rows affected (0.01 sec)

mysql> 
mysql> ALTER TABLE test_bug 
    ->   ADD INDEX index_consult_order (consult_order_id) ;
Query OK, 0 rows affected (0.01 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql> 
mysql> ALTER TABLE test_bug 
    ->   ADD INDEX index_right_no (right_no) ;
Query OK, 0 rows affected (0.00 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql> 
mysql> ALTER TABLE test_bug 
    ->   AUTO_INCREMENT = 100000000 ;
Query OK, 0 rows affected (0.00 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql> 
mysql> show create table  test_bug;
  
   CREATE TABLE `test_bug` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `consult_order_id` bigint(20) DEFAULT NULL ,
  `pay_channel` int(11) DEFAULT NULL COMMENT ,
  `price` bigint(20) DEFAULT NULL COMMENT ,
  `trade_no` varchar(64) DEFAULT NULL COMMENT ,
  `right_no` varchar(64) DEFAULT NULL COMMENT ,
  `item_id` bigint(20) NOT NULL COMMENT ,
  `source_type` int(11) NOT NULL COMMENT ,
  `gmt_create` datetime DEFAULT CURRENT_TIMESTAMP ,
  `gmt_modified` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP ,
  PRIMARY KEY (`id`),
  KEY `index_consult_order` (`consult_order_id`),
  KEY `index_right_no` (`right_no`)
) ENGINE=InnoDB AUTO_INCREMENT=100000000 DEFAULT CHARSET=utf8  


1 row in set (0.00 sec)

mysql> show create table test_bug; 

   CREATE TABLE `test_bug` (
  `id` BIGINT (20) NOT NULL AUTO_INCREMENT,
  `consult_order_id` BIGINT (20) DEFAULT NULL,
  `pay_channel` INT (11) DEFAULT NULL,
  `price` BIGINT (20) DEFAULT NULL,
  `trade_no` VARCHAR (64) DEFAULT NULL,
  `right_no` VARCHAR (64) DEFAULT NULL,
  `item_id` BIGINT (20) NOT NULL,
  `source_type` INT (11) NOT NULL,
  `gmt_create` DATETIME DEFAULT CURRENT_TIMESTAMP,
  `gmt_modified` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`),
  KEY `index_consult_order` (`consult_order_id`),
  KEY `index_right_no` (`right_no`)
) ENGINE = INNODB DEFAULT CHARSET = utf8 

1 row in set (0.00 sec)