这个sql语句怎么写?

[dropping]

DECLARE @STR VARCHAR(4000)
DECLARE @email VARCHAR(50)
DECLARE @gulid VARCHAR(30)
SET @gulid='rosamond.liu'
DECLARE c_at Cursor
FOR
--SET @STR = 'SELECT EMAIL FROM OPENQUERY(ODB,''' + 'SELECT EMAIL FROM GUID_ACCOUNT WHERE GULID = ''''' + @gulid + ''''''')'
SELECT EMAIL FROM OPENQUERY(ODB,'SELECT EMAIL FROM GUID_ACCOUNT WHERE GULID = ''''' + @gulid + '''''')
OPEN c_at
 FETCH NEXT FROM c_at INTO @email
  WHILE (@@FETCH_STATUS = 0) 
BEGIN
PRINT @email
END

结果显示:
伺服器: 訊息 170，層級 15，狀態 1，行 8
行 8: '+' 附近的語法不正確。
----------------------------------------------
这里的'是怎么个用法?麻烦解释下.

[dawugui]

动态sql语句基本语法 
1 :普通SQL语句可以用Exec执行 

eg:   Select * from tableName 
         Exec('select * from tableName') 
         Exec sp_executesql N'select * from tableName'    -- 请注意字符串前一定要加N 

2:字段名，表名，数据库名之类作为变量时，必须用动态SQL 

eg:   
declare @fname varchar(20) 
set @fname = 'FiledName' 
Select @fname from tableName              -- 错误,不会提示错误，但结果为固定值FiledName,并非所要。 
Exec('select ' + @fname + ' from tableName')     -- 请注意 加号前后的 单引号的边上加空格 

当然将字符串改成变量的形式也可 
declare @fname varchar(20) 
set @fname = 'FiledName' --设置字段名 

declare @s varchar(1000) 
set @s = 'select ' + @fname + ' from tableName' 
Exec(@s)                -- 成功 
exec sp_executesql @s   -- 此句会报错 



declare @s Nvarchar(1000)  -- 注意此处改为nvarchar(1000) 
set @s = 'select ' + @fname + ' from tableName' 
Exec(@s)                -- 成功     
exec sp_executesql @s   -- 此句正确 

3. 输出参数 
declare @num int, 
        @sqls nvarchar(4000) 
set @sqls='select count(*) from tableName' 
exec(@sqls) 
--如何将exec执行结果放入变量中？ 

declare @num int, 
               @sqls nvarchar(4000) 
set @sqls='select @a=count(*) from tableName ' 
exec sp_executesql @sqls,N'@a int output',@num output 
select @num 

[dropping]

类似这样的例子,中间的引号是怎么个用法?

[dawugui]

SELECT EMAIL FROM OPENQUERY(ODB,'SELECT EMAIL FROM GUID_ACCOUNT WHERE GULID = ''' + @gulid + ''')

[-狙击手-]

DECLARE @STR VARCHAR(4000)
DECLARE @email VARCHAR(50)
DECLARE @gulid VARCHAR(30)
SET @gulid='rosamond.liu'
DECLARE c_at Cursor
FOR
--SET @STR = 'SELECT EMAIL FROM OPENQUERY(ODB,''' + 'SELECT EMAIL FROM GUID_ACCOUNT WHERE GULID = ''''' + @gulid + ''''''')'
SELECT EMAIL FROM OPENQUERY(ODB,'SELECT EMAIL FROM GUID_ACCOUNT WHERE GULID = ''' + @gulid + '''')
OPEN c_at
 FETCH NEXT FROM c_at INTO @email
  WHILE (@@FETCH_STATUS = 0) 
BEGIN
PRINT @email
END

[dropping]

SELECT EMAIL FROM OPENQUERY(ODB,'SELECT EMAIL FROM GUID_ACCOUNT WHERE GULID = ''' + @gulid + ''')

这句不对.

[dropping]

TO:无枪狙击手

伺服器: 訊息 170，層級 15，狀態 1，行 8
行 8: '+' 附近的語法不正確。

[nohypo]

关键是把
+ @gulid +
改为
+cast (@gulid as nvarchar(20))+
因为nvarchar()是动态sql的参数类型

[dropping]

TO：nohypo
怎么涉及到nvarchar()呢？

[w2jc]

4楼第8行应该没有问题。

LZ在5楼里面引用的那句明显就是错的，少了一个单引号，和5楼的不一样嘛。

[dropping]

5楼那个我是复制3楼的,
4楼的我完全复制过来运行了一次,错误提示在6楼.
问题转变下.

DECLARE @STR NVARCHAR(4000)
DECLARE @email VARCHAR(50)
DECLARE @gulid NVARCHAR(30)
SET @gulid='rosamond.liu'

SET @STR ='SELECT GULID,EMAIL FROM OPENQUERY(ODB,''' + 'SELECT GULID,EMAIL FROM GUID_ACCOUNT WHERE GULID = ''''' + @gulid + ''''''')'

PRINT @STR
EXEC (@STR)

这样会输出一条有GUID,EMAIL的记录.
我怎么把这个GUID,EMAIL分别赋值为两个变量?

[dropping]

搞定,代码如下:

DECLARE @STR NVARCHAR(4000)
DECLARE @gulid VARCHAR(30)
SET @gulid='rosamond.liu'

SET @STR ='SELECT @mail= EMAIL FROM OPENQUERY(ODB,''' + 'SELECT EMAIL FROM GUID_ACCOUNT WHERE GULID = ''''' + @gulid + ''''''')'

DECLARE @email VARCHAR(50)
exec sp_executesql @STR,N'@mail VARCHAR(50) OUT,@email OUT
print @email

[dropping]

上面的少了个引号.

DECLARE @STR NVARCHAR(4000)
DECLARE @gulid VARCHAR(30)
SET @gulid='rosamond.liu'

SET @STR ='SELECT @mail= EMAIL FROM OPENQUERY(ODB,''' + 'SELECT EMAIL FROM GUID_ACCOUNT WHERE GULID = ''''' + @gulid + ''''''')'

DECLARE @email VARCHAR(50)
exec sp_executesql @STR,N'@mail VARCHAR(50) OUT',@email OUT
print @email