数据库的管理

• 查看当前所有的数据库： show databases;
• 创建数据库：create database 数据库名 DEFAULT CHARSET utf8 COLLATE utf8_general_ci;

　　　　create database day25db;

　　　　create database day25db DEFAULT CHARSET utf8 COLLATE utf8_general_ci;

• 删除数据库：drop database 数据库名;

• 进入数据（进入文件）：use 数据库;

示例：

# 1.登录MySQL
wupeiqi@wupeiqideMBP ~ % /usr/local/mysql/bin/mysql -u root -p
Enter password:
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 5
Server version: 5.7.31 MySQL Community Server (GPL)

Copyright (c) 2000, 2020, 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.

# 2.查看当前数据库
mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
4 rows in set (0.00 sec)

# 3. 创建数据库:  create database 数据库名 default charset 编码 collate 排序规则;
mysql> create database db1 default charset utf8 collate utf8_general_ci;
Query OK, 1 row affected (0.00 sec)

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| db1                |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
5 rows in set (0.01 sec)

# 4. 删除数据库
mysql> drop database db1;
Query OK, 0 rows affected (0.00 sec)

# 5. 查看当前数据库
mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
4 rows in set (0.00 sec)

# 6. 进入数据库
mysql> use mysql;
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
# 7. 进入mysql数据库（文件夹），查看此数据库下的所有表。
mysql> show tables;

mysql> show tables;
+---------------------------+
| Tables_in_mysql           |
+---------------------------+
| columns_priv              |
| db                        |
| engine_cost               |
| event                     |
| func                      |
| general_log               |
| gtid_executed             |
|········|          |
+---------------------------+
31 rows in set (0.00 sec)

# 8. 退出
mysql>exit;