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HomeDatabaseMysql Tutorialsqlserver利用存储过程去除重复行的sql语句

以前弄过类似,去除相同信息的方法,现在找不到了,不过今天又花一些时间给弄出来了,记录一下

还是先上代码吧 ,可以先看
代码如下:
ALTER procedure [dbo].[PROC_ITEMMASTER_GETUNIQUE] @PAGEINDEX INT,@uid int,@itemnumber varchar(50)
AS
begin tran --开始事务
drop table [ItemMaster].[dbo].[testim] --删除表
--把不重复记录转存到testim中
select * into [ItemMaster].[dbo].[testim] from [ItemMaster].[dbo].[dat_item_master] where item_uid in(select min(item_uid) as item_uid from [ItemMaster].[dbo].[dat_item_master] group by item_number) and status=0
select top 10 * from [ItemMaster].[dbo].[testim] where item_uid not in (select top (10*(@PAGEINDEX-1)) item_uid from [ItemMaster].[dbo].[testim])
and owneruid=@uid and item_number like @itemnumber+'%'

--判断是否出错
if @@error0
begin
rollback tran --出错则回滚
end
else
begin --否则提前事务
commit tran
end

我的数据是这样的:因为item_uid是标识列,item_number有重复的,

我想过滤成这样:

顺带说几个在编程的时候遇到的小问题

1.程序 出现 Could not find stored procedure 找不到这个存储过程

因为我的程序数据库有四个,而默认连接是A,但实际要执行B库里的存储过程,导致出错,

解决办法1:可在A里面建个一样的存储过程2:在执行连接的时候,替换下数据库就行了

2. asp.net/C# 将存储过程中返回的数据集,填充到dataset/datatable


代码如下:
SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["SolutionSQLServer"].ToString());
SqlCommand cmd = new SqlCommand("Test",conn);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("@MaxId", SqlDbType.Int).Value = 12000;

SqlDataAdapter sda = new SqlDataAdapter(cmd);
DataTable dt = new DataTable();
sda.Fill(dt);


在这感谢 http://www.cnblogs.com/liujuncm5/archive/2009/08/31/1557569.html

3.在存储过程里面,写SQL语句不能动态不加order by 功能

比如

代码如下:
--·@new_orderby 是传入参数,不能这样写
select top (10*(2-1)) item_uid from testim order by @new_orderby


--执行这个的时候,SQL会出现 The SELECT item identified by the ORDER BY number 1 contains a variable as part
of the expression identifying a column position. Variables are only allowed when
ordering by an expression referencing a column name.

不过我找到解决办法,不过很麻烦,

(第二个回答用 ' sql '进行连接)

(用case end 也行)

4. select into 和 insert into select 两种复制文句 (这里感谢)

  1.

语句形式为:

  2.

语句形式为:

5.顺便复习下常用的SQL方法语句
代码如下:
declare @name varchar(200) --声明变量
set @name='abcd;def' --赋值
print 'exec len :'+Convert(varchar(10),Len(@name)) --convert(type,value)转换,Len(value)获取大小
print 'exec charindex:'+Convert(varchar(10),CharIndex('e',@name))--CharIndex(find,value) 在value中查找find的位置
print 'not replace:'+@name
print 'exec replace:'+Replace(@name,';','') --用replace替换
print 'exec substring:'+Substring(@name,0,3)--用substring截取
print @@RowCount --返回上一行代码受影响的行数

作者:

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