對miek這個賬號localhost 授予了所有庫，所表的select權限

mysql> grant select on *.* to ‘mike‘@‘localhost‘;
Query OK, 0 rows affected (0.00 sec)

mysql> exit
Bye
[root@mysql ~]# mysql -umike -p123
Warning: Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end
 
 with ; or \g.
Your MySQL connection id is 4
Server version: 5.6.36 Source distribution

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mysql> 
mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| company            |
| db1                |
| db2                |
| db3                |
 

| db4                |
| db5                |
| db6                |
| mysql              |
| performance_schema |
| test               |
| test2              |
| test_1             |
+--------------------+
13 rows in set (0.04 sec)




mysql> use db1;
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> show tables;
+---------------+
| Tables_in_db1 |
+---------------+
| innodb__t_t1  |
| innodb__t_t2  |
| innodb__t_t3  |
| innodb__t_t4  |
| t1            |
| t3            |
+---------------+
6 rows in set (0.00 sec)

mysql> select * from t1;
+------+------+--------+------+
| id   | name | sex    | age  |
+------+------+--------+------+
|    1 | mike | male   |   15 |
|    2 | alex | female |   16 |
|    3 | NULL | NULL   | NULL |
|    4 | NULL | NULL   | NULL |
+------+------+--------+------+
4 rows in set (0.01 sec)

mysql> desc t1;
+-------+-----------------------+------+-----+---------+-------+
| Field | Type                  | Null | Key | Default | Extra |
+-------+-----------------------+------+-----+---------+-------+
| id    | int(11)               | YES  |     | NULL    |       |
| name  | varchar(50)           | YES  |     | NULL    |       |
| sex   | enum(‘male‘,‘female‘) | YES  |     | NULL    |       |
| age   | int(4)                | YES  |     | NULL    |       |
+-------+-----------------------+------+-----+---------+-------+
4 rows in set (0.00 sec)

mysql> insert into t1 values(5,‘jack‘,‘male‘,50);
ERROR 1142 (42000): INSERT command denied to user ‘mike‘@‘localhost‘ for table ‘t1‘

沒有插入記錄權限，只有select權限

mysql 權限管理 對所有庫 所有表 授權 *.*