字段加密

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如何实现对数据库单个字段进行加密 选择自 callzjy 的 Blog
关键字 callzjy 字段加密 sqlserver 函数
出处

create view v_rand

as

select c=unicode(cast(round(rand()*255,0) as tinyint))

go

create function f_jmstr(@str varchar(8000),@type bit)returns varchar(8000)

/*

*参数说明

*str:要加密的字符串或已经加密后的字符

*type:操作类型--0加密--解密

*返回值说明

*当操作类型为加密时(type--0):返回为加密后的str,即存放于数据库中的字符串

*当操作类型为解密时(type--1):返回为实际字符串,即加密字符串解密后的原来字符串

*/

As

begin

declare @re varchar(8000)--返回值

declare @c int--加密字符

declare @i int

/*

*加密方法为原字符异或一个随机ASCII字符

*/
if @type=0--加密
begin
select @c=c,@re='',@i=len(@str) from v_rand
while @i>0
select @re=nchar(unicode(substring(@str,@i,1))^@c^@i)+@re
,@i=@i-1
set @re=@re+nchar(@c)
end
else--解密
begin
select @i=len(@str)-1,@c=unicode(substring(@str,@i+1,1)),@re=''
while @i>0
select @re=nchar(unicode(substring(@str,@i,1))^@c^@i)+@re ,@i=@i-1
end
return(@re)
end
go
--测试
declare @tempstr varchar(20)
set @tempstr=' 1 2 3aA'
select dbo.f_jmstr(dbo.f_jmstr(@tempstr,0),1)
输出结果
1 2 3aA
(完)
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让数据库产生一张详细的日历表

也许有了这张表，你的工作会轻松很多！

CREATE TABLE [dbo].[time_dimension] (
[time_id] [int] IDENTITY (1, 1) NOT NULL ,
[the_date] [datetime] NULL ,
[the_day] [nvarchar] (15) NULL ,
[the_month] [nvarchar] (15) NULL ,
[the_year] [smallint] NULL ,
[day_of_month] [smallint] NULL ,
[week_of_year] [smallint] NULL ,
[month_of_year] [smallint] NULL ,
[quarter] [nvarchar] (2) NULL ,
[fiscal_period] [nvarchar] (20) NULL
) ON [PRIMARY]

DECLARE @WeekString varchar(12),
@dDate SMALLDATETIME,
@sMonth varchar(20),
@iYear smallint,
@iDayOfMonth smallint,
@iWeekOfYear smallint,
@iMonthOfYear smallint,
@sQuarter varchar(2),
@sSQL varchar(100),
@adddays int

SELECT @adddays = 1 --日期增量（可以自由设定）
SELECT @dDate = '01/01/2002' --开始日期

WHILE @dDate < '12/31/2004' --结束日期
BEGIN

SELECT @WeekString = DATENAME (dw, @dDate)
SELECT @sMonth=DATENAME(mm,@dDate)
SELECT @iYear= DATENAME (yy, @dDate)
SELECT @iDayOfMonth=DATENAME (dd, @dDate)
SELECT @iWeekOfYear= DATENAME (week, @dDate)
SELECT @iMonthOfYear=DATEPART(month, @dDate)
SELECT @sQuarter = 'Q' + CAST(DATENAME (quarter, @dDate)as varchar(1))

INSERT INTO time_dimension(the_date, the_day, the_month, the_year,
day_of_month,
week_of_year, month_of_year, quarter) VALUES
(@dDate, @WeekString, @sMonth, @iYear, @iDayOfMonth, @iWeekOfYear,
@iMonthOfYear, @sQuarter)
SELECT @dDate = @dDate + @adddays
END
GO

select * from time_dimension

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--搜索某个字符串在那个表的那个字段中
declare @str varchar(100)
set @str='White' --要搜索的字符串
declare @s varchar(8000)
declare tb cursor local for
select s='if exists(select 1 from ['+b.name+'] where ['+a.name+'] like ''%'+@str+'%'')
print ''所在的表及字段: ['+b.name+'].['+a.name+']'''
from syscolumns a join sysobjects b on a.id=b.id
where b.xtype='U' and a.status>=0
and a.xusertype in(175,239,231,167)
open tb
fetch next from tb into @s
while @@fetch_status=0
begin
exec(@s)
fetch next from tb into @s
end
close tb
deallocate tb
/*--测试结果
所在的表及字段: [authors].[au_lname]
--*/
======================================================================================
--查询指定的表在那些数据库中存在

declare @tbname sysname
set @tbname='客户资料'

declare @dbname sysname,@sql nvarchar(4000),@re bit,@sql1 varchar(8000)
set @sql1=''
declare tb cursor for select name from master..sysdatabases
open tb
fetch next from tb into @dbname
while @@fetch_status=0
begin
set @sql='set @re=case when exists(select 1 from ['
+@dbname+']..sysobjects where xtype=''U'' and name='''
+@tbname+''') then 1 else 0 end'
exec sp_executesql @sql,N'@re bit out',@re out
if @re=1 set @sql1=@sql1+' union all select '''+@dbname+''''
fetch next from tb into @dbname
end
close tb
deallocate tb
set @sql1=substring(@sql1,12,8000)
exec(@sql1)

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比较两个数据库的表结构差异 选择自 zjcxc 的 Blog
关键字 表结构,差异
出处

/*--比较两个数据库的表结构差异

--*/
/*--调用示例

exec p_comparestructure 'xzkh_model','xzkh_new'
--*/

if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[p_comparestructure]') and OBJECTPROPERTY(id, N'IsProcedure') = 1)
drop procedure [dbo].[p_comparestructure]
GO

create proc p_comparestructure
@dbname1 varchar(250), --要比较的数据库名1
@dbname2 varchar(250) --要比较的数据库名2
as
create table #tb1(表名1 varchar(250),字段名 varchar(250),序号 int,标识 bit,主键 bit,类型 varchar(250),
占用字节数 int,长度 int,小数位数 int,允许空 bit,默认值 varchar(500),字段说明 varchar(500))

create table #tb2(表名2 varchar(250),字段名 varchar(250),序号 int,标识 bit,主键 bit,类型 varchar(250),
占用字节数 int,长度 int,小数位数 int,允许空 bit,默认值 varchar(500),字段说明 varchar(500))

--得到数据库1的结构
exec('insert into #tb1 SELECT
表名=d.name,字段名=a.name,序号=a.colid,
标识=case when a.status=0x80 then 1 else 0 end,
主键=case when exists(SELECT 1 FROM '+@dbname1+'..sysobjects where xtype=''PK'' and name in (
SELECT name FROM '+@dbname1+'..sysindexes WHERE indid in(
SELECT indid FROM '+@dbname1+'..sysindexkeys WHERE id = a.id AND colid=a.colid
))) then 1 else 0 end,
类型=b.name, 占用字节数=a.length,长度=a.prec,小数位数=a.scale, 允许空=a.isnullable,
默认值=isnull(e.text,''''''),字段说明=isnull(g.[value],'''''')
FROM '+@dbname1+'..syscolumns a
left join '+@dbname1+'..systypes b on a.xtype=b.xusertype
inner join '+@dbname1+'..sysobjects d on a.id=d.id and d.xtype=''U'' and d.name<>''dtproperties''
left join '+@dbname1+'..syscomments e on a.cdefault=e.id
left join '+@dbname1+'..sysproperties g on a.id=g.id and a.colid=g.smallid
order by a.id,a.colorder')

--得到数据库2的结构
exec('insert into #tb2 SELECT
表名=d.name,字段名=a.name,序号=a.colid,
标识=case when a.status=0x80 then 1 else 0 end,
主键=case when exists(SELECT 1 FROM '+@dbname2+'..sysobjects where xtype=''PK'' and name in (
SELECT name FROM '+@dbname2+'..sysindexes WHERE indid in(
SELECT indid FROM '+@dbname2+'..sysindexkeys WHERE id = a.id AND colid=a.colid
))) then 1 else 0 end,
类型=b.name, 占用字节数=a.length,长度=a.prec,小数位数=a.scale, 允许空=a.isnullable,
默认值=isnull(e.text,''''''),字段说明=isnull(g.[value],'''''')
FROM '+@dbname2+'..syscolumns a
left join '+@dbname2+'..systypes b on a.xtype=b.xusertype
inner join '+@dbname2+'..sysobjects d on a.id=d.id and d.xtype=''U'' and d.name<>''dtproperties''
left join '+@dbname2+'..syscomments e on a.cdefault=e.id
left join '+@dbname2+'..sysproperties g on a.id=g.id and a.colid=g.smallid
order by a.id,a.colorder')
--and not exists(select 1 from #tb2 where 表名2=a.表名1)
select 比较结果=case when a.表名1 is null and b.序号=1 then '库1缺少表：'+b.表名2
when b.表名2 is null and a.序号=1 then '库2缺少表:'+a.表名1
when a.字段名 is null and exists(select 1 from #tb1 where 表名1=b.表名2) then '库1 ['+b.表名2+'] 缺少字段：'+b.字段名
when b.字段名 is null and exists(select 1 from #tb2 where 表名2=a.表名1) then '库2 ['+a.表名1+'] 缺少字段：'+a.字段名
when a.标识<>b.标识 then '标识不同'
when a.主键<>b.主键 then '主键设置不同'
when a.类型<>b.类型 then '字段类型不同'
when a.占用字节数<>b.占用字节数 then '占用字节数'
when a.长度<>b.长度 then '长度不同'
when a.小数位数<>b.小数位数 then '小数位数不同'
when a.允许空<>b.允许空 then '是否允许空不同'
when a.默认值<>b.默认值 then '默认值不同'
when a.字段说明<>b.字段说明 then '字段说明不同'
else '' end,
*
from #tb1 a
full join #tb2 b on a.表名1=b.表名2 and a.字段名=b.字段名
where a.表名1 is null or a.字段名 is null or b.表名2 is null or b.字段名 is null
or a.标识<>b.标识 or a.主键<>b.主键 or a.类型<>b.类型
or a.占用字节数<>b.占用字节数 or a.长度<>b.长度 or a.小数位数<>b.小数位数
or a.允许空<>b.允许空 or a.默认值<>b.默认值 or a.字段说明<>b.字段说明
order by isnull(a.表名1,b.表名2),isnull(a.序号,b.序号)--isnull(a.字段名,b.字段名)
go
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