您好,登录后才能下订单哦!
这篇文章主要介绍了Mac上如何实现终端管理MySQL数据库,具有一定借鉴价值,需要的朋友可以参考下。希望大家阅读完这篇文章后大有收获。下面让小编带着大家一起了解一下。
打开终端输入如下命令:
/usr/local/MySQL/bin/mysql -u root -p
其中root为用户名。
这时会出现如下命令:
Enter password:
此时如果你没有改密码,直接敲回车。否则,输入你的密码。
这样就可以访问你的数据库服务器了。
数据表的基
1.1 create 创建数据库
create database firstDB;
1.2 show 查看所有数据库
mysql> show databases;+--------------------+| Database | +--------------------+| information_schema | | firstDB | | mysql | | performance_schema |+--------------------+rows in set (0.00 sec)
1.3 alter 修改数据库
alter 命令修改数据库编码:
默认创建的数据库默认不支持中文字符,如果我们需要它支持中文字符,则将它的编码设置为utf8格式:
mysql> ALTER DATABASE testDB CHARACTER SET UTF8;Query OK, 1 row affected (0.00 sec)
1.4 use 使用数据库
mysql> use firstDB; Database changed
1.5 查看当前使用的数据库
mysql> select database(); +------------+| database() | +------------+| firstdb | +------------+1 row in set (0.00 sec)
1.6 drop 删除数据库
mysql> drop database firstDB; Query OK, 0 rows affected (0.00 sec)
我们首先创建一个数据库,提供我们往后的使用:
mysql> create database testDB;Query OK, 1 row affected (0.00 sec)
创建后记得用use命令进入(使用)数据库,不然后面的操作都会不成功的。
2.1 create 创建表
mysql> create table PEOPLE ( -> ID int AUTO_INCREMENT PRIMARY KEY, -> NAME varchar(20) not null, -> AGE int not null, -> BIRTHDAY datetime); Query OK, 0 rows affected (0.01 sec)
2.2 show 显示表
显示当前数据库所有的数据表
mysql> show tables; +------------------+| Tables_in_testdb | +------------------+| PEOPLE | +------------------+1 row in set (0.00 sec)
2.3 desc 查看表结构
mysql> desc PEOPLE -> ; +----------+-------------+------+-----+---------+----------------+| Field | Type | Null | Key | Default | Extra | +----------+-------------+------+-----+---------+----------------+| ID | int(11) | NO | PRI | NULL | auto_increment | | NAME | varchar(20) | NO | | NULL | | | AGE | int(11) | NO | | NULL | | | BIRTHDAY | datetime | YES | | NULL | | +----------+-------------+------+-----+---------+----------------+ 4 rows in set (0.01 sec)
2.4 alter 修改表结构(增、删、改)
默认创建的表不支持中文字符,所以需将表编码设置为utf8:
mysql> ALTER TABLE KEYCHAIN CONVERT TO CHARACTER SET UTF8; Query OK, 1 row affected (0.02 sec) Records: 1 Duplicates: 0 Warnings: 0
2.4.1 insert 在表中添加列(字段)
mysql> alter table PEOPLE add star BOOL;Query OK, 0 rows affected (0.02 sec)Records: 0 Duplicates: 0 Warnings: 0
提示:在MySQL里,布尔类型会自动转换为tinyint(1)类型。
我们不妨使用desc去查看一下PEOPLE表结构:
mysql> desc PEOPLE; +----------+-------------+------+-----+---------+----------------+| Field | Type | Null | Key | Default | Extra | +----------+-------------+------+-----+---------+----------------+| ID | int(11) | NO | PRI | NULL | auto_increment | | NAME | varchar(20) | NO | | NULL | | | AGE | int(11) | NO | | NULL | | | BIRTHDAY | datetime | YES | | NULL | | | star | tinyint(1) | YES | | NULL | | +----------+-------------+------+-----+---------+----------------+ 5 rows in set (0.00 sec)
现在,你该相信我了吧?
2.4.2 alter 修改表(列)字段
mysql> alter table PEOPLE MODIFY star int;Query OK, 0 rows affected (0.01 sec)Records: 0 Duplicates: 0 Warnings: 0
也可以指定 int(n) 的长度,比如 int(2)。
我们再次使用desc查看PEOPLE表结构:
mysql> desc PEOPLE; +----------+-------------+------+-----+---------+----------------+| Field | Type | Null | Key | Default | Extra | +----------+-------------+------+-----+---------+----------------+| ID | int(11) | NO | PRI | NULL | auto_increment | | NAME | varchar(20) | NO | | NULL | | | AGE | int(11) | NO | | NULL | | | BIRTHDAY | datetime | YES | | NULL | | | star | int(11) | YES | | NULL | | +----------+-------------+------+-----+---------+----------------+ 5 rows in set (0.00 sec)
2.4.3 delete 删除表(列)字段
mysql> alter table PEOPLE DROP column star;Query OK, 0 rows affected (0.02 sec)Records: 0 Duplicates: 0 Warnings: 0
删除后,再次查看PEOPLE表结构:
mysql> desc PEOPLE; +----------+-------------+------+-----+---------+----------------+| Field | Type | Null | Key | Default | Extra | +----------+-------------+------+-----+---------+----------------+| ID | int(11) | NO | PRI | NULL | auto_increment | | NAME | varchar(20) | NO | | NULL | | | AGE | int(11) | NO | | NULL | | | BIRTHDAY | datetime | YES | | NULL | | +----------+-------------+------+-----+---------+----------------+ 4 rows in set (0.00 sec)
删除字段成功,现在我们已经不能看到star的字段了。
2.4.4 rename 重命名表名
mysql> RENAME TABLE PEOPLE TO NEW_PEOPLE; Query OK, 0 rows affected (0.00 sec)
2.4.5 null or not null
修改表字段允许为空或不允许为空:
mysql> ALTER TABLE PEOPLE MODIFY AGE INT(3) NULL; Query OK, 0 rows affected (0.01 sec)Records: 0 Duplicates: 0 Warnings: 0
把 PEOPLE 表的 AGE 字段设置成“允许为空”,即插入记录时这个字段可以不录入。否则相反。
它的格式为:ALTER TABLE MODIFY
mysql> create table newTable select * from PEOPLE; Query OK, 0 rows affected (0.01 sec) Records: 0 Duplicates: 0 Warnings: 0
我们查看一下目前数据库存在的表:
mysql> show tables; +------------------+| Tables_in_testdb | +------------------+| PEOPLE || newTable | +------------------+2 rows in set (0.00 sec)
本操作,包含增、删、改、查数据。
以下命令均在PEOPLE表上操作。
3.1 增加数据(增)
PEOPLE表目前是没有数据的,它是空的数据表,我们现在先添加一些数据。
insert into 命令添加数据:
mysql> insert into PEOPLE VALUES (null, 'Anny', 22, '1992-05-22'); Query OK, 1 row affected (0.00 sec)
使用select命令查看表(会在后面介绍),现在我们查看PEOPLE数据表的数据:
mysql> select * from PEOPLE; +----+------+-----+---------------------+| ID | NAME | AGE | BIRTHDAY | +----+------+-----+---------------------+| 1 | Anny | 22 | 1992-05-22 00:00:00 | +----+------+-----+---------------------+1 row in set (0.00 sec)
数据表现在有一条数据。
我们多添加几条数据,如:
mysql> select * from PEOPLE; +----+--------+-----+---------------------+| ID | NAME | AGE | BIRTHDAY | +----+--------+-----+---------------------+| 1 | Anny | 22 | 1992-05-22 00:00:00 | | 2 | Garvey | 23 | 1991-05-22 00:00:00 | | 3 | Lisa | 25 | 1989-05-22 00:00:00 | | 4 | Nick | 24 | 1990-05-22 00:00:00 || 5 | Rick | 24 | 1991-05-22 00:00:00 | +----+--------+-----+---------------------+5 rows in set (0.00 sec)
3.2 删除数据(删)
delete 命令删除数据:
mysql> delete from PEOPLE where name = 'Lisa'; Query OK, 1 row affected (0.01 sec)
再次查询PEOPLE表:
mysql> select * from PEOPLE; +----+--------+-----+---------------------+| ID | NAME | AGE | BIRTHDAY | +----+--------+-----+---------------------+| 1 | Anny | 22 | 1992-05-22 00:00:00 | | 2 | Garvey | 23 | 1991-05-22 00:00:00 | | 4 | Nick | 24 | 1990-05-22 00:00:00 || 5 | Rick | 24 | 1991-05-22 00:00:00 | +----+--------+-----+---------------------+4 rows in set (0.00 sec)
已经看不到名为“Lisa”的数据了。
3.3 修改数据(改)
update 命令修改数据:
mysql> update PEOPLE set name='Calvin' where name = 'Garvey'; Query OK, 1 row affected (0.00 sec)Rows matched: 1 Changed: 1 Warnings: 0
查询PEOPLE表内容:
mysql> select * from PEOPLE; +----+--------+-----+---------------------+| ID | NAME | AGE | BIRTHDAY | +----+--------+-----+---------------------+| 1 | Anny | 22 | 1992-05-22 00:00:00 | | 2 | Calvin | 23 | 1991-05-22 00:00:00 | | 4 | Nick | 24 | 1990-05-22 00:00:00 || 5 | Rick | 24 | 1991-05-22 00:00:00 | +----+--------+-----+---------------------+4 rows in set (0.00 sec)
名为“Garvey”的记录已经修改为“Calvin”。
3.4 查询数据(查)
select 命令查询数据,最简单的就是查询表的所有数据,也就是我们最初使用到的那条命令:
mysql> select * from PEOPLE; +----+--------+-----+---------------------+| ID | NAME | AGE | BIRTHDAY | +----+--------+-----+---------------------+| 1 | Anny | 22 | 1992-05-22 00:00:00 | | 2 | Calvin | 23 | 1991-05-22 00:00:00 | | 4 | Nick | 24 | 1990-05-22 00:00:00 || 5 | Rick | 24 | 1991-05-22 00:00:00 | +----+--------+-----+---------------------+4 rows in set (0.00 sec)
格式:select * from <表名>,*代表所有字段。
查询数据时也可指定显示的(列)字段:
mysql> select NAME, AGE, BIRTHDAY from PEOPLE; +--------+-----+---------------------+| NAME | AGE | BIRTHDAY | +--------+-----+---------------------+| Anny | 22 | 1992-05-22 00:00:00 | | Calvin | 23 | 1991-05-22 00:00:00 | | Nick | 24 | 1990-05-22 00:00:00 || Rick | 24 | 1991-05-22 00:00:00 | +--------+-----+---------------------+4 rows in set (0.00 sec)
格式:select <字段名,字段名,…> from <表名>。
select查询命令还有很多的高级用法,比如用来查找不重复(distinct)的数据,使数据按条件排序(order by),按查询条件显示数据(where)等等。这些都会在下一篇文章作重点介绍,请大家继续留意我的博客,谢谢。
4.1 创建视图
视图是从数据库里导出一个或多个表的虚拟表,是用来方便用户对数据的操作。
mysql> CREATE VIEW PEOPLE_VIEW ( -> NAME, AGE) -> AS SELECT NAME, AGE FROM PEOPLE;
创建成功后查看视图。
PEOPLE PEOPLE.AGE PEOPLE.BIRTHDAY PEOPLE.ID PEOPLE.NAME mysql> SELECT * FROM PEOPLE_VIEW -> ;+--------+-----+ | NAME | AGE | +--------+-----+ | Anny | 22 | | Calvin | 23 | | Nick | 24 | | Rick | 24 | +--------+-----+4 rows in set (0.00 sec)
我们也可以使用 DESC 命令查看视图的结构。
mysql> DESC PEOPLE_VIEW; +-------+---------+------+-----+---------+-------+| Field | Type | Null | Key | Default | Extra | +-------+---------+------+-----+---------+-------+| ID | int(11) | NO | | 0 | | +-------+---------+------+-----+---------+-------+1 row in set (0.01 sec)
4.2 替换视图
创建或替换原有视图。
mysql> CREATE OR REPLACE VIEW PEOPLE_VIEW(PEOPLE_ID,PEOPLE_NAME,PEOPLE_AGE) AS SELECT ID,NAME,AGE FROM PEOPLE; Query OK, 0 rows affected (0.00 sec)
创建或替换后查看视图。
mysql> SELECT * FROM PEOPLE_VIEW; +-----------+-------------+------------+| PEOPLE_ID | PEOPLE_NAME | PEOPLE_AGE | +-----------+-------------+------------+| 1 | Anny | 22 | | 2 | Calvin | 23 | | 4 | Nick | 24 || 5 | Rick | 24 | +-----------+-------------+------------+4 rows in set (0.00 sec)
4.3 操作视图
当视图数据有变化时(增、删、改),真实的表数据也会随着改变。也就是说,对视图的操作就是对表的数据,所以我们可以把视图当作表。
例:往视图插入一条数据。
mysql> INSERT INTO PEOPLE_VIEW VALUES(NULL, 'Kerry', '33'); Query OK, 1 row affected (0.00 sec)
插入数据成功后查看视图。
mysql> SELECT * FROM PEOPLE_VIEW ; +-----------+-------------+------------+| PEOPLE_ID | PEOPLE_NAME | PEOPLE_AGE | +-----------+-------------+------------+| 1 | Anny | 22 | | 2 | Calvin | 23 | | 4 | Nick | 24 | | 5 | Rick | 24 || 6 | Kerry | 33 | +-----------+-------------+------------+5 rows in set (0.00 sec)
可以在视图上看到我们刚刚插入的数据,现在我们就来验证一下真实的表是否也会作出变化。
mysql> SELECT * FROM PEOPLE; +----+--------+-----+---------------------+| ID | NAME | AGE | BIRTHDAY | +----+--------+-----+---------------------+| 1 | Anny | 22 | 1992-05-22 00:00:00 | | 2 | Calvin | 23 | 1991-05-22 00:00:00 | | 4 | Nick | 24 | 1990-05-22 00:00:00 | | 5 | Rick | 24 | 1991-05-22 00:00:00 || 6 | Kerry | 33 | NULL | +----+--------+-----+---------------------+5 rows in set (0.00 sec)
可见,真实的表数据也已经有所改变,刚刚往视图里插入的那一条数据存在于真实表中,真理便是:对视图的操作就是对表的数据。
4.4 删除视图
mysql> DROP VIEW PEOPLE_VIEW;Query OK, 0 rows affected (0.00 sec)
感谢你能够认真阅读完这篇文章,希望小编分享Mac上如何实现终端管理MySQL数据库内容对大家有帮助,同时也希望大家多多支持亿速云,关注亿速云行业资讯频道,遇到问题就找亿速云,详细的解决方法等着你来学习!
免责声明:本站发布的内容(图片、视频和文字)以原创、转载和分享为主,文章观点不代表本网站立场,如果涉及侵权请联系站长邮箱:is@yisu.com进行举报,并提供相关证据,一经查实,将立刻删除涉嫌侵权内容。