我遇到了我的一个老项目（使用mysql 5和php5.5）。我只是想用mysql 8和php7.0测试这个项目。要安装db，我通常会执行以下操作：

...
mysql -u root -p < DBinstall/webAppDBinstall.sql
...

在我的web应用的“安装”脚本中。sql命令包含：

...
-- # ######################## SET PHP_SCRIPT & GRANTS FOR ############################
CREATE USER 'php_script'@'localhost' IDENTIFIED BY 'php_script';
GRANT INSERT,SELECT ON webApp.* TO 'php_script'@'localhost';
GRANT UPDATE ON webApp.Orders TO 'php_script'@'localhost';
GRANT UPDATE ON webApp.OrderItems TO 'php_script'@'localhost';
GRANT UPDATE ON webApp.UserStatus TO 'php_script'@'localhost';
GRANT INSERT ON webApp.History TO 'php_script'@'localhost';
...

然后我在运行webapp时从php得到以下错误： $ cat /var/log/apache2/error.log ```
...
[Thu May 28 06:01:26.317867 2020] [:error] [pid 8906] [client 127.0.0.1:32960] PHP Warning: mysqli::query(): Couldn't fetch mysqli in /var/www/webApp/src_php/mylib.php on line 68, referer: http://webApp/index.php?error=0
...

注意：这个项目使用mysql 5和php5运行得非常完美。
然后我觉得“闻起来”就像是特权问题。所以我做了以下工作：

mysql> select User,Table_name,Table_priv from mysql.tables_priv where User='php_script';
+------------+------------+------------+
| User | Table_name | Table_priv |
+------------+------------+------------+
| php_script | History | Insert |
| php_script | OrderItems | Update |
| php_script | Orders | Update |
| php_script | UserStatus | Update |
+------------+------------+------------+
4 rows in set (0.00 sec)

mysql>

### 是的，就是这样。

证据如下：
我改变了主意 `DBinstall/webAppDBinstall.sql` 脚本来自：

...
-- # ######################## SET PHP_SCRIPT & GRANTS FOR ############################
CREATE USER 'php_script'@'localhost' IDENTIFIED BY 'php_script';
GRANT INSERT,SELECT ON webApp.* TO 'php_script'@'localhost';
GRANT UPDATE ON webApp.Orders TO 'php_script'@'localhost';
GRANT UPDATE ON webApp.OrderItems TO 'php_script'@'localhost';
GRANT UPDATE ON webApp.UserStatus TO 'php_script'@'localhost';
GRANT INSERT ON webApp.History TO 'php_script'@'localhost';
...

收件人：

-- # ######################## SET PHP_SCRIPT & GRANTS FOR ############################
CREATE USER 'php_script'@'localhost' IDENTIFIED BY 'php_script';
GRANT INSERT,SELECT ON webApp.Users TO 'php_script'@'localhost';
GRANT INSERT,SELECT ON webApp.UserStatus TO 'php_script'@'localhost';
GRANT INSERT,SELECT ON webApp.Categories TO 'php_script'@'localhost';
GRANT INSERT,SELECT ON webApp.ProductGroups TO 'php_script'@'localhost';
GRANT INSERT,SELECT ON webApp.CategoriesGroups TO 'php_script'@'localhost';
GRANT INSERT,SELECT ON webApp.Products TO 'php_script'@'localhost';
GRANT INSERT,SELECT ON webApp.Orders TO 'php_script'@'localhost';
GRANT INSERT,SELECT ON webApp.OrderItems TO 'php_script'@'localhost';
GRANT INSERT,SELECT ON webApp.Messages TO 'php_script'@'localhost';
GRANT INSERT,SELECT ON webApp.History TO 'php_script'@'localhost';
GRANT UPDATE ON webApp.Orders TO 'php_script'@'localhost';
GRANT UPDATE ON webApp.OrderItems TO 'php_script'@'localhost';
GRANT UPDATE ON webApp.UserStatus TO 'php_script'@'localhost';
GRANT INSERT ON webApp.History TO 'php_script'@'localhost';

结果是：

mysql> select User,Table_name,Table_priv from mysql.tables_priv where User='php_script';
+------------+------------------+----------------------+
| User | Table_name | Table_priv |
+------------+------------------+----------------------+
| php_script | History | Select,Insert |
| php_script | Categories | Select,Insert |
| php_script | CategoriesGroups | Select,Insert |
| php_script | Messages | Select,Insert |
| php_script | OrderItems | Select,Insert,Update |
| php_script | Orders | Select,Insert,Update |
| php_script | ProductGroups | Select,Insert |
| php_script | Products | Select,Insert |
| php_script | UserStatus | Select,Insert,Update |
| php_script | Users | Select,Insert |
+------------+------------------+----------------------+
10 rows in set (0.00 sec)

mysql>

#### 关于“为什么在grants中使用通配符”还有更好的想法吗？？？

（抱歉重复我的问题，但stackoverflow禁止我回答自己的问题）
我的问题是：为什么 `GRANT <PRIVS> ON <DB>.* TO <USER>;` 通配符语法已停止“工作”
注意：此问题与mysqli:：query（）不同：无法获取mysqli。我的webapp应用程序是一个在mysql 5.x部署下完美运行的系统。它与php无关（尽管 `mysqli` 错误似乎存在，但事实并非如此）。