SQLserver数据库基础
1控制数据库的服务 运行cmd 在控制面板输入netstart MSSQLserver(启动数据库服务) 在控制面板输入netstop MSSQLserver(关闭数据库服务) 在控制面板输入netcontinueMSSQLserver(继续数据库服务) 【字母大小写均可】 2数据库文件类型 .Mdf是数据库文件 .Ldf 是
1·控制数据库的服务
运行 cmd
在控制面板输入 net start MSSQLserver (启动数据库服务)
在控制面板输入 net stop MSSQLserver (关闭数据库服务)
在控制面板输入 net continue MSSQLserver (继续数据库服务)
【字母大小写均可】
2·数据库文件类型
. Mdf 是数据库文件
. Ldf 是数据库操作日志
. Ndf 是数据库次要文件(一般没用)
3·sql常用的数据类型
Char(10) 字符型,10表示字节长度,可更改
Datetime 日期时间型
Decimal(18,0) 浮点型,18表示整数位个数,可更改;0表示小数位个数,可更改
Float 浮点型,精确到15位小数
Image 文本图形型,用于存储大量的二进制数据,通常为图形等ole和嵌入对象
Int 整型
Text 文本图形型,用于存储大量文本数据
Varchar(50) 字符型
Varchar(MAX) 字符型
Xml
4·创建数据库、表
create database qq --创建数据库
go
use qq --选择数据库
go
create table shuiguo --创建表
(
Code int,--列名+数据类型,英文逗号分隔
Name char(10),
Jiage decimal(18.2),
Chandi char(10)
)
5·删除数据库 drop database qq
6·修改数据库名,前面为旧名字,后面为新名字 sp_renamedb qq,abc
7·备份与还原
数据库的备份
右键数据库名--->任务--->备份--->备份类型选择完整、仅复制备份、备份集过期时间晚于随便一个天数--->附加--->选择路径、写文件名和后缀.bak--->确定
数据库的还原
右键数据库中的还原数据库--->目标数据库的名字要和备份的数据库名字一致--->源设备、选择备份后数据库的路径、选择并确定
8·分离与附加
数据库的分离
右键要分离的数据库名--->任务--->分离(删除链接、更新统计信息)--->确定
数据库的附加
右键数据库附加--->添加(寻找数据库路径)--->确定

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