1、说明:创建数据库
CREATE
DATABASE
database-name
2、说明:删除数据库
drop
database
dbname
3、说明:备份sql
server
---
创建
备份数据的
device
USE
master
EXEC
sp_addumpdevice
'disk',
'testBack',
'c:\mssql7backup\MyNwind_1.dat'
---
开始
备份
BACKUP
DATABASE
pubs
TO
testBack
4、说明:创建新表
create
table
tabname(col1
type1
[not
null]
[primary
key],col2
type2
[not
null],..)
根据已有的表创建新表:
A:create
table
tab_new
like
tab_old
(使用旧表创建新表)
B:create
table
tab_new
as
select
col1,col2…
from
tab_old
definition
only
5、说明:
删除新表:drop
table
tabname
6、说明:
增加一个列:Alter
table
tabname
add
column
col
type
注:列增加后将不能删除。DB2中列加上后数据类型也不能改变,唯一能改变的是增加varchar类型的长度。
7、说明:
添加主键:Alter
table
tabname
add
primary
key(col)
说明:
删除主键:Alter
table
tabname
drop
primary
key(col)
8、说明:
创建索引:create
[unique]
index
idxname
on
tabname(col….)
删除索引:drop
index
idxname
注:索引是不可更改的,想更改必须删除重新建。
9、说明:
创建视图:create
view
viewname
as
select
statement
删除视图:drop
view
viewname
10、说明:几个简单的基本的sql语句
选择:select
*
from
table1
where
范围
插入:insert
into
table1(field1,field2)
values(value1,value2)
删除:delete
from
table1
where
范围
更新:update
table1
set
field1=value1
where
范围
查找:select
*
from
table1
where
field1
like
’%value1%’
---like的语法很精妙,查资料!
排序:select
*
from
table1
order
by
field1,field2
[desc]
总数:select
count
*
as
totalcount
from
table1
求和:select
sum(field1)
as
sumvalue
from
table1
平均:select
avg(field1)
as
avgvalue
from
table1
最大:select
max(field1)
as
maxvalue
from
table1
最小:select
min(field1)
as
minvalue
from
table1
简单方便的方法就是使用excel中的查找功能,在查找值中输入你需要查找的值,查找范围为值,然后全部查找,ctrl+a全选,接下来点击鼠标右键,选择删除,然后删除整行。如下面录制的 *** 作,查找姓名为A1的,然后删除整行:删除本地图片首先获得图片的路径
string address="路径"
FileInfo file = new FileInfo(address)
file.delete()
增加就直接保存图片框里面的图片就OK了
SaveFileDialog fileone = new SaveFileDialog()
fileone.OverwritePrompt = true
fileone.Filter = "BMP文件|*.bmp|GIF文件|*.gif|JPG文件|*.jpg|PNG文件|*.png|ICO文件|*.ico|所有文件|*.*"
fileone.FilterIndex = 1
fileone.ShowDialog()
if (fileone.FilterIndex == 1)
{
this.picBox.Image.Save(fileone.FileName, System.Drawing.Imaging.ImageFormat.Bmp)
userHelper.iniSuffix = ".bmp"
}
else if (fileone.FilterIndex == 2)
{
this.picBox.Image.Save(fileone.FileName, System.Drawing.Imaging.ImageFormat.Gif)
userHelper.iniSuffix = ".gif"
}
else if (fileone.FilterIndex == 3)
{
this.picBox.Image.Save(fileone.FileName, System.Drawing.Imaging.ImageFormat.Jpeg)
userHelper.iniSuffix = ".jpg"
}
else if (fileone.FilterIndex == 4)
{
this.picBox.Image.Save(fileone.FileName, System.Drawing.Imaging.ImageFormat.Png)
userHelper.iniSuffix = ".png"
}
else
{
this.picBox.Image.Save(fileone.FileName, System.Drawing.Imaging.ImageFormat.Icon)
userHelper.iniSuffix = ".ico"
}
userHelper.iniAddress = fileone.FileName
toolStripTextBox1.Text = fileone.FileName
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