employees

供练习sql使用。mysql同样提供了employees数据库，但并未随数据库一起安装，其下载链接也极其隐蔽，可能导致许多人没注意到。

下载地址：https://launchpad.net/test-db/employees-db-1/1.0.6

建议大家下载：employees_db-full-1.0.6.tar.bz2，解压缩，进入目录，并导入。

tar -xjf $HOME/Downloads/employees_db-full-1.0.4.tar.bz2

//解压缩，进入目录

cd employees_db/

//导入数据库root为用户名

mysql -t -u root -p < employees.sqlroot@storm-master-01:/home/employees_db#mysql -h ip -t -u username -p password -P3306 < employees.sql

mysql: [Warning] Using a password on the command line interface can be insecure.

+-----------------------------+

| INFO                        |

+-----------------------------+

| CREATING DATABASE structURE |

+-----------------------------+

+---------------------+

| INFO                |

+---------------------+

| LOADING departments |

+---------------------+

+-------------------+

| INFO              |

+-------------------+

| LOADING employees |

+-------------------+

ERROR 2006 (HY000) at line 1 in file: 'load_employees.dump': MySQL server has gone awayMySQL max_allowed_packet设置及问题

1、修改mysqld的配置文件my.cnf

调整max_allowed_packet的值，修改为5M就比较合适了。[mysqld]

port = 3308

socket = /dev/shm/mysqld.sock

skip-external-locking

key_buffer_size = 16M

max_allowed_packet = 10M

table_open_cache = 64

sort_buffer_size = 512K

net_buffer_length = 8K

read_buffer_size = 256K

read_rnd_buffer_size = 512K

myisam_sort_buffer_size = 8M

2、修改[mysqld]中的值[mysqldump]

quick

max_allowed_packet = 10M

By default this is relatively small.mysql> show global variables like 'max_allowed_packet';

+--------------------+---------+

| Variable_name | Value |

+--------------------+---------+

| max_allowed_packet | 1048576 |

+--------------------+---------+

1 row in set (0.00 sec)

You can increase, for example to 16M with:mysql> set global max_allowed_packet=1024*1024*16;

mysql> show global variables like 'max_allowed_packet';

+--------------------+----------+

| Variable_name | Value |

+--------------------+----------+

| max_allowed_packet | 16777216 |

+--------------------+----------+

1 row in set (0.00 sec)

附件create table emp (

empno numeric(4) not null,

ename varchar(10),

job varchar(9),

mgr numeric(4),

hiredate datetime,

sal numeric(7, 2),

comm numeric(7, 2),

deptno numeric(2)

);

insert into emp values (7369, 'SMITH', 'CLERK', 7902, '1980-12-17', 800, null, 20);

insert into emp values (7499, 'ALLEN', 'SALESMAN', 7698, '1981-02-20', 1600, 300, 30);

insert into emp values (7521, 'WARD', 'SALESMAN', 7698, '1981-02-22', 1250, 500, 30);

insert into emp values (7566, 'JONES', 'MANAGER', 7839, '1981-04-02', 2975, null, 20);

insert into emp values (7654, 'MARTIN', 'SALESMAN', 7698, '1981-09-28', 1250, 1400, 30);

insert into emp values (7698, 'BLAKE', 'MANAGER', 7839, '1981-05-01', 2850, null, 30);

insert into emp values (7782, 'CLARK', 'MANAGER', 7839, '1981-06-09', 2450, null, 10);

insert into emp values (7788, 'SCOTT', 'ANALYST', 7566, '1982-12-09', 3000, null, 20);

insert into emp values (7839, 'KING', 'PRESIDENT', null, '1981-11-17', 5000, null, 10);

insert into emp values (7844, 'TURNER', 'SALESMAN', 7698, '1981-09-08', 1500, 0, 30);

insert into emp values (7876, 'ADAMS', 'CLERK', 7788, '1983-01-12', 1100, null, 20);

insert into emp values (7900, 'JAMES', 'CLERK', 7698, '1981-12-03', 950, null, 30);

insert into emp values (7902, 'FORD', 'ANALYST', 7566, '1981-12-03', 3000, null, 20);

insert into emp values (7934, 'MILLER', 'CLERK', 7782, '1982-01-23', 1300, null, 10);

create table dept (

deptno numeric(2),

dname varchar(14),

loc varchar(13)

);

insert into dept values (10, 'ACCOUNTING', 'NEW YORK');

insert into dept values (20, 'RESEARCH', 'DALLAS');

insert into dept values (30, 'SALES', 'CHICAGO');

insert into dept values (40, 'OPERATIONS', 'BOSTON');

create table bonus (

empno numeric(4),

job varchar(9),

sal numeric,

comm numeric

);

create table salgrade (

grade numeric,

losal numeric,

hisal numeric

);

insert into salgrade values (1, 700, 1200);

insert into salgrade values (2, 1201, 1400);

insert into salgrade values (3, 1401, 2000);

insert into salgrade values (4, 2001, 3000);

insert into salgrade values (5, 3001, 9999);

文章最后发布于: 2018-05-30 10:36:48

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