登陆数据库:
# [mysql dir]/bin/mysql -h hostname -u root -p
创建一个数据库:
mysql> create database [databasename];
列出所有数据库:
mysql> show databases;
切换到一个数据库:
mysql> use [db name];
显示一个数据库的所有表:
mysql> show tables;
查看数据表的字段格式:
mysql> describe [table name];
删除一个数据库:
mysql> drop database [database name];
删除一个数据表:
mysql> drop table [table name];
显示一个数据表的所有数据:
mysql> SELECT * FROM [table name];
返回指定数据表的各列信息:
mysql> show columns from [table name];
使用值“whatever”过滤显示选定的某些行:
mysql> SELECT * FROM [table name] WHERE [field name] = "whatever";
显示所有包含name为”Bob”和phone number为“3444444”的记录:
mysql> SELECT * FROM [table name] WHERE name = "Bob" AND phone_number = '3444444';
显示所有不包含name为”Bob”和phone number为“3444444”的记录,并以phone_number字段排序:
mysql> SELECT * FROM [table name] WHERE name != "Bob" AND phone_number = '3444444' order by phone_number;
显示所有的name以字母“bob”开头和phone number为“3444444”的记录:
mysql> SELECT * FROM [table name] WHERE name like "Bob%" AND phone_number = '3444444';
显示name以字母“bob”开头和phone number为“3444444”的第1至第5条记录:
mysql> SELECT * FROM [table name] WHERE name like "Bob%" AND phone_number = '3444444' limit 1,5;
使用正则表达式查找记录:使用“正则表达式二进制”强制区分大小写:此命令查找以a开头的任何记录:
mysql> SELECT * FROM [table name] WHERE rec RLIKE "^a";
返回唯一不同的记录:
mysql> SELECT DISTINCT [column name] FROM [table name];
以升序或降序显示选定的记录:
mysql> SELECT [col1],[col2] FROM [table name] ORDER BY [col2] DESC;
返回行数:
mysql> SELECT COUNT(*) FROM [table name];
统计指定列值的总和:
mysql> SELECT SUM(*) FROM [table name];
联结表:
mysql> select lookup.illustrationid, lookup.personid,person.birthday from lookup left join person on lookup.personid=person.personid=statement to join birthday in person table with primary illustration id;
新建一个用户:以root登录:切换到mysql数据库,创建用户,刷新权限:
# mysql -u root -p
mysql> use mysql;
mysql> INSERT INTO user (Host,User,Password) VALUES('%','username',PASSWORD('password'));
mysql> flush privileges;
从unix命令行更改用户密码:
# [mysql dir]/bin/mysqladmin -u username -h hostname.blah.org -p password 'new-password'
从mysql命令行更改用户密码:以root登录,设置密码,更新权限:
# /etc/init.d/mysql stop
# mysqld_safe --skip-grant-tables &
# mysql -u root
mysql> use mysql;
mysql> update user set password=PASSWORD("newrootpassword") where User='root';
mysql> flush privileges;
mysql> quit
# /etc/init.d/mysql stop
# /etc/init.d/mysql start
root密码为空时,设置root密码:
# mysqladmin -u root password newpassword
更新root密码:
# mysqladmin -u root -p oldpassword newpassword
允许用户“bob”从localhost以密码“passwd”连接服务器:以root登录,切换mysql数据库:设置权限,更新权限:
# mysql -u root -p
mysql> use mysql;
mysql> grant usage on *.* to bob@localhost identified by 'passwd';
mysql> flush privileges;
为数据库db设置权限:以root登录,切换到mysql数据库,授予权限,更新权限:
# mysql -u root -p
mysql> use mysql;
mysql> INSERT INTO db (Host,Db,User,Select_priv,Insert_priv,Update_priv,Delete_priv,Create_priv,Drop_priv) VALUES ('%','databasename','username','Y','Y','Y','Y','Y','N');
mysql> flush privileges;
或者
mysql> grant all privileges on databasename.* to username@localhost;
mysql> flush privileges;
更新已存在表的数据:
mysql> UPDATE [table name] SET Select_priv = 'Y',Insert_priv = 'Y',Update_priv = 'Y' where [field name] = 'user';
删除表中[field name] = ‘whatever’的行:
mysql> DELETE from [table name] where [field name] = 'whatever';
更新数据库的权限/特权:
mysql> flush privileges;
删除列:
mysql> alter table [table name] drop column [column name];
新增列到db:
mysql> alter table [table name] add column [new column name] varchar (20);
更改列名:
mysql> alter table [table name] change [old column name] [new column name] varchar (50);
增加唯一的列:
mysql> alter table [table name] add unique ([column name]);
设置列值大点:
mysql> alter table [table name] modify [column name] VARCHAR(3);
删除唯一列:
mysql> alter table [table name] drop index [colmn name];
导入一个CSV文件到表:
mysql> LOAD DATA INFILE '/tmp/filename.csv' replace INTO TABLE [table name] FIELDS TERMINATED BY ',' LINES TERMINATED BY 'n' (field1,field2,field3);
导出所有数据库到sql文件:
# [mysql dir]/bin/mysqldump -u root -ppassword --opt >/tmp/alldatabases.sql
导出一个数据库:
# [mysql dir]/bin/mysqldump -u username -ppassword --databases databasename >/tmp/databasename.sql
从一个数据库导出一个表:
# [mysql dir]/bin/mysqldump -c -u username -ppassword databasename tablename > /tmp/databasename.tablename.sql
从sql文件还原数据库(数据表):
# [mysql dir]/bin/mysql -u username -ppassword databasename < /tmp/databasename.sql
创建数据表例1:
mysql> CREATE TABLE [table name] (firstname VARCHAR(20), middleinitial VARCHAR(3), lastname VARCHAR(35),suffix VARCHAR(3),officeid VARCHAR(10),userid VARCHAR(15),username VARCHAR(8),email VARCHAR(35),phone VARCHAR(25), groups VARCHAR(15),datestamp DATE,timestamp time,pgpemail VARCHAR(255));
创建数据表例2:
mysql> create table [table name] (personid int(50) not null auto_increment primary key,firstname varchar(35),middlename varchar(50),lastnamevarchar(50) default 'bato');