Basic operations on invisible columns in MySQL 8.0

CREATE TABLE `t2` (
  `id` int NOT NULL AUTO_INCREMENT,
  `name` varchar(20) DEFAULT NULL,
  `age` int DEFAULT NULL INVISIBLE,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci

mysql> alter table t2 add score int invisible;
Query OK, 0 rows affected (0.05 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> show create table t1\G
*************************** 1. row ***************************
Table: t1
Create Table: CREATE TABLE `t1` (
`id` int NOT NULL AUTO_INCREMENT,
`name` varchar(20) DEFAULT NULL,
`age` int DEFAULT NULL /*!80023 INVISIBLE */,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci
1 row in set (0.00 sec)

mysql> create table t3 like t1;
Query OK, 0 rows affected (0.09 sec)

mysql> show create table t3\G
*************************** 1. row ***************************
Table: t3
Create Table: CREATE TABLE `t3` (
`id` int NOT NULL AUTO_INCREMENT,
`name` varchar(20) DEFAULT NULL,
`age` int DEFAULT NULL /*!80023 INVISIBLE */,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci
1 row in set (0.00 sec)

mysql> insert into t1 values ​​(1,'zhangsan',10);
ERROR 1136 (21S01): Column count doesn't match value count at row 1

mysql> insert into t1 (id,name,age) values ​​(1,'zhangsan',10);
 Query OK, 1 row affected (0.01 sec)

mysql> select * from t1;
+----+----------+
| id | name |
+----+----------+
| 1 | zhangsan |
+----+----------+
1 row in set (0.00 sec)

mysql> select id,name,age from t1;
+----+----------+------+
| id | name | age |
+----+----------+------+
| 1 | zhangsan | 10 |
+----+----------+------+
1 row in set (0.00 sec)

HERE TABLE_SCHEMA = 'test' AND TABLE_NAME = 't1';
+------------+-------------+-----------+
| TABLE_NAME | COLUMN_NAME | EXTRA |
+------------+-------------+-----------+
| t1 | i | |
| t1 | j | |
| t1 | k | INVISIBLE |
+------------+-------------+-----------+

mysql> desc test.t1;
+-------+-------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+----------------+
| id | int | NO | PRI | NULL | auto_increment |
| name | varchar(20) | YES | | NULL | |
| age | int | YES | | NULL | INVISIBLE |
+-------+-------------+------+-----+---------+----------------+
3 rows in set (0.00 sec)

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> create table t4 (id int not null auto_increment primary key invisible,name varchar(20),age int );
Query OK, 0 rows affected (0.07 sec)

mysql> insert into t4 values ​​('zhangsan',10),('lisi',15);
Query OK, 2 rows affected (0.01 sec)
Records: 2 Duplicates: 0 Warnings: 0

mysql> select * from t4;
+----------+------+
| name | age |
+----------+------+
| zhangsan | 10 |
| lisi | 15 |
+----------+------+
2 rows in set (0.00 sec)