数据库数据复制

/*--数据库数据复制

 将一个数据库中的数据复制到另一个数据库
 如果某列在目标数据库中为标识列,将不会被复制

 适用范围:数据库结构发生了变化,想将旧数据库进行升级
  这样就可以根据新的数据库结构创建一个空库,然后
  将旧数据库的所有数据复制到新库中
--*/

/*--调用示例

 exec p_copydb '源数据库','目标数据库'
 exec p_copydb 'acc_五医','acc_演示数据8'
--*/

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

create proc p_copydb
@o_dbname sysname,  --要复制数据的数据库--源数据库
@n_dbname sysname,  --接收数据的数据库--目标数据库
@cleardb bit=0   --清空目标数据库
as
declare @sql nvarchar(4000)

--禁用约束,防止复制时的数据冲突
set @sql='declare #tbc cursor for select name,tbname=object_name(parent_obj)
 from '+@n_dbname+'..sysobjects where xtype in(''C'',''F'')'
exec(@sql)
declare @name sysname,@tbname sysname
open #tbc
fetch next from #tbc into @name,@tbname
while @@fetch_status=0
begin
 set @sql='alter table '+@n_dbname+'..['+@tbname+'] NOCHECK CONSTRAINT ['+@name+']'
 exec(@sql)
 fetch next from #tbc into @name,@tbname
end
close #tbc

--复制数据
declare @sql1 varchar(8000)
set @sql='declare #tb cursor for select a.name from '
 +@o_dbname+'..sysobjects a inner join '
 +@n_dbname+'..sysobjects b on a.name=b.name
  where a.xtype=''U'' and b.xtype=''U'''
exec(@sql)
open #tb
fetch next from #tb into @tbname
while @@fetch_status=0
begin
 select @sql1=''
  ,@sql='select @sql1=@sql1+'',[''+a.name+'']'' from(
  select name from '+@o_dbname+'..syscolumns where id in
  (select id from '+@o_dbname+'..sysobjects where name='''+@tbname+''')
 ) a inner join (
  select name from '+@n_dbname+'..syscolumns where status<>0x80 and id in
  (select id from '+@n_dbname+'..sysobjects where name='''+@tbname+''')
 ) b on a.name=b.name'
 exec sp_executesql @sql,N'@sql1 nvarchar(4000) out',@sql1 out

 select @sql1=substring(@sql1,2,8000)
 exec('insert into '+@n_dbname+'..['+@tbname+']('+@sql1
  +') select '+@sql1+' from '+@o_dbname+'..['+@tbname+']')
 if @@error<>0
  print('insert into '+@n_dbname+'..['+@tbname+']('+@sql1
   +') select '+@sql1+' from '+@o_dbname+'..['+@tbname+']')
 fetch next from #tb into @tbname
end
close #tb
deallocate #tb

--数据复制完成后启用约束
open #tbc
fetch next from #tbc into @name,@tbname
while @@fetch_status=0
begin
 set @sql='alter table '+@n_dbname+'..['+@tbname+'] CHECK CONSTRAINT ['+@name+']'
 exec(@sql)
 fetch next from #tbc into @name,@tbname
end
close #tbc
deallocate #tbc
go