如何使用mysql数据库基本命令添加数据库

如何使用mysql数据库基本命令添加数据库，相信很多没有经验的人对此束手无策，为此本文总结了问题出现的原因和解决方法，通过这篇文章希望你能解决这个问题。

添加数据库

[root@localhost ~]# mysql -uroot -p   #进入mysql数据表`Enter password: Welcome to the MySQL monitor.  Commands end with ; or \g.Your MySQL connection id is 8......  #省略部分内容Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> show databases;+--------------------+| Database           |+--------------------+| information_schema || mysql              || performance_schema || sys                |+--------------------+4 rows in set (0.00 sec)

mysql> create database school; #创建新库'school
Query OK, 1 row affected (0.00 sec)

mysql> show databases; #查看所有库
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| school |
| sys |
+--------------------+
5 rows in set (0.00 sec)

添加数据表

mysql>use school;mysql> create table info (id int not null,name char(6),score decimal(5,2),age int(4))；Query OK, 0 rows affected (0.04 sec)mysql> desc info;   #查看表结构+-------+--------------+------+-----+---------+-------+| Field | Type         | Null | Key | Default | Extra |+-------+--------------+------+-----+---------+-------+| id       | int(11)      | NO   |     | NULL    |       || name  | char(6)   | YES  |     | NULL    |       || score | decimal(5,2) | YES  |  NULL   |       || age   | int(4)        | YES  |     | NULL    |       |+-------+--------------+------+-----+---------+-------+添加数据表内容mysql> insert into info (id,name,score,age)values(1,'张三',88,33);Query OK, 1 row affected (0.01 sec)mysql> insert into info (id,name,score,age)values(2,'李四',48,31);Query OK, 1 row affected (0.01 sec)mysql> insert into info (id,name,score,age)values(3,'王五',68,27);Query OK, 1 row affected (0.00 sec)mysql> select * from info;   #查看表内容+----+--------+-------+------+| id | name   | score | age  |+----+--------+-------+------+|  1 | 张三   | 88.00 |   33 ||  2 | 李四   | 48.00 |   31 ||  3 | 王五   | 68.00 |   27 |+----+--------+-------+------+添加表列mysql> alter table info add column score decimal(5,2);Query OK, 0 rows affected (0.05 sec)Records: 0  Duplicates: 0  Warnings: 0mysql> select * from info;   #查看表内容+----+--------+--------+-------+| id | name   | hobbly | score |+----+--------+--------+-------+|  1 | zl        | 看书   |  NULL ||  2 | 李四   | 上网   |  NULL ||  5 | kl        | 游泳   |  NULL |+----+--------+--------+-------+更改数据mysql> update info set score=82 where id=1;  #更改id=1的学生成绩为82分Query OK, 1 row affected (0.01 sec)Rows matched: 1  Changed: 1  Warnings: 0mysql> select * from info;  #查看更改效果+----+--------+-------+------+| id | name   | score | age  |+----+--------+-------+------+|  1 | 张三   | 82.00 |   33 ||  2 | 李四   | 48.00 |   31 ||  3 | 王五   | 68.00 |   27 |+----+--------+-------+------+删除数据表mysql> drop table info;Query OK, 0 rows affected (0.02 sec)mysql> show tables;     #查看是否删除Empty set (0.00 sec)     #已经删除（空表）删除库mysql> drop database school;Query OK, 0 rows affected (0.01 sec)mysql> show databases;     #查看school数据库是否删除+--------------------+| Database           |+--------------------+| information_schema || mysql              || performance_schema || sys                |+--------------------+删除表列（记录条数）mysql> delete from info where hobbly=1;Query OK, 1 row affected (0.01 sec)mysql> select * from info;+----+--------+-------+------+--------+| id | name   | score | age  | hobbly |+----+--------+-------+------+--------+|  1 | 张三   | 82.00 |   33 |     3        ||  2 | 李四   | 48.00 |   31 |     5      ||  3 | 王五   | 68.00 |   27 |      4    ||  2 | ff        |  55      | 44  |      2     ||  3 |ww      | 33       |3 1  |     3      |+----+--------+-------+------+--------+删除表列（字段）mysql> select * from info;  #查看数据表+----+--------+-------+--------+| id | name   | score | hobbly |+----+--------+-------+--------+|  1 | zl        | 88       | 看书   ||  2 | 李四    | 68      | 上网   ||  5 | kl        | 88       | 游泳   |+----+--------+-------+--------+mysql> alter table info drop column score;   #用alter删除表列mysql> select * from info; #再次查看数据表+----+--------+--------+| id | name   | hobbly |+----+--------+--------+|  1 | zl         | 看书   ||  2 | 李四    | 上网   ||  5 | kl         | 游泳   |+----+--------+--------+

看完上述内容，你们掌握如何使用mysql数据库基本命令添加数据库的方法了吗？如果还想学到更多技能或想了解更多相关内容，欢迎关注行业资讯频道，感谢各位的阅读！