mysql create dabase 語法詳解

由於SQL標准的存在，各個關系型數據庫管理系統中創建庫的語句都差不多

 

一、mysql 中創建數據庫的語法如下：

　　1、創建數據庫的語法：

create {database  | schema } [if not exists] db_name [create_specification]
-- mysql在以在創建庫的時候指定庫的默認字符集，
create_specification:
    [defualt] character set  [=] charset_name
    [default] collate        [=] collation_name

 

二、mysql中創建數據庫要有create 權限：

　　1、創建一個叫coder的用戶

mysql:root> create user coder@'127.0.0.1' identified by '123456';
Query OK, 0 rows affected (0.00 sec)

　　2、coder去創建庫時會報錯(權限不足)

mysql:coder> show grants;
+-------------------------------------------+
| Grants for coder@127.0.0.1                |
+-------------------------------------------+
| GRANT USAGE ON *.* TO 'coder'@'127.0.0.1' |
+-------------------------------------------+
1 row in set (0.00 sec)

mysql:coder> create database coderdba;
ERROR 1044 (42000): Access denied for user 'coder'@'127.0.0.1' to database 'coderdba'

 　　3、用root用戶給coder用戶加上create權限

mysql:root> grant create on *.* to coder@'127.0.0.1';
Query OK, 0 rows affected (0.00 sec)

　　4、coder用戶重新發起連接、然后就可以創建庫了

mysql -ucoder -h127.0.0.1 -P3306 -p123456
mysql: [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 7
Server version: 5.7.18-enterprise-commercial-advanced-log MySQL Enterprise Server - Advanced Edition (Commercial)

Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql:coder> create database coderdba;
Query OK, 1 row affected (0.00 sec)

 

三、mysql數據庫權限的一些吐槽：

　　1、mysql權限好的地方就在於它權限的層次分明

　　2、mysql權限不好的地方就在於它的權限粒度不是非學細、比如說上面的例子，事實上我要的是一個create database 權限

　　但是可惜呀它沒有這么細的，它只有一個create ；但是只要在實例級別給了create 那么就是說它可以create everthing啦。

 

 

----