Question

我有以下代码检查物理文件计数以确认先前的进程已生成正确数量的文件（在不同的文件夹中）

set NOCOUNT ON

declare @DateOffset int

set @DateOffset=0

-- Create a table variable to store user data
DECLARE @myTable TABLE
(
    docID INT IDENTITY(1,1),
    docRef VARCHAR(10),
    YPTMPID varchar(3),
    saveDir VARCHAR(500),
    totalLettersExpected int,
    actualLetters int 
);

insert @myTable SELECT docRef, YPTMPID,
    saveDir=max(Save_Directory) + cast(YEAR(GETDATE()-@DateOffset) as varchar(4)) + '\'  + datename(month, GETDATE()-@DateOffset) + '\'+SUBSTRING(CONVERT(CHAR(20), GETDATE()-@DateOffset, 101),4, 2) + '.' + LEFT(CONVERT(CHAR(20), GETDATE()-@DateOffset, 101), 2)
    + '.' + SUBSTRING(CONVERT(CHAR(20), GETDATE()-@DateOffset, 101),7, 4),
    COUNT(*) as 'Total Letters', null
  FROM [alpsMaster].[dbo].[uExtractMonitor]
  group by docRef, YPTMPID
  order by 1,2



-- Get the number of rows in the looping table
DECLARE @RowCount INT, @SQL nvarchar(4000), @LoopSQL nvarchar(4000), @Date varchar(20)

set @Date=rtrim(CONVERT( CHAR(12), getDate()-@DateOffset, 106)) --'29 Oct 2013'
SET @RowCount = (SELECT COUNT(docID) FROM @myTable) 

-- Declare an iterator
DECLARE @I INT

-- Initialize the iterator
SET @I = 1

-- Loop through the rows of table @myTable, and for each docRef, check the file directory for the correct number of files
WHILE (@I <= @RowCount)
    BEGIN
        DECLARE @docRef VARCHAR(10), @saveDir VARCHAR(500), @TemplateID varchar(3), @letterCount int
        DECLARE @statement nvarchar(200), @EQRecordCout int

        -- Get the data from table and set to variables
        SELECT @docRef = docref FROM @myTable WHERE docID = @I
        SELECT @saveDir = saveDir FROM @myTable WHERE docID = @I        
        SELECT @TemplateID = YPTMPID FROM @myTable WHERE docID = @I 

        update @myTable set actualLetters = 0 where docRef=@docRef

        create table #files (subdirectory varchar(100), depth int, [file] int)
        insert into #files  EXEC master.sys.xp_dirtree @saveDir,0,1;    

        -- *** PROBLEM HERE ***
        set @statement= 'SELECT count(*) FROM BOCTEST.S653C36C.LIVEBOC_A.' + @docRef
        print @statement

        exec @EQRecordCout=sp_executesql @statement
        print @EQRecordCout

        select @letterCount = COUNT(*) from #files 
        print cast(@letterCount as char(3)) + '  files for ' + @docRef 
        drop table #files
        update @myTable set actualLetters = @letterCount where docRef=@docRef-- and YPTMPID=@TemplateID

        -- Increment the iterator
        SET @I = @I  + 1        

END

select * from @myTable

set NOCOUNT OFF

在我的最终WHILE LOOP内部我希望使用动态SQL计算iSeries远程服务器上每个文件中的记录数（在SQL字符串末尾的表名为docRef为动态）

但即使它执行得很好，我进入变量 @EQRecordCout 的所有内容都是零。这是不正确的，虽然有些表是空的，但大多数都有记录

写这个以返回值的正确方法是什么？

set @statement= 'SELECT count(*) FROM BOCTEST.S653C36C.LIVEBOC_A.' + @docRef
print @statement

exec @EQRecordCout=sp_executesql @statement
print @EQRecordCout

感谢菲利普

Answer 1

您需要将output参数与此{/ 1}}一起使用

sp_Executesql

点击此处： Extract value returned from dynamic SQL

Answer 2

您可以将sp_executesql与output参数一起使用。请务必指定output两次：

set @statement= 'SELECT @rc = count(*) FROM BOCTEST.S653C36C.LIVEBOC_A.' + @docRef

declare @rc int
exec sp_executesql @statement, N'@rc int output', @rc output;

Answer 3

我在Microsoft Technet: sp_executesql (Transact-SQL)

MS Technet Library 找到了答案

这是有效的WHILE LOOP代码：

WHILE (@I <= @RowCount)
    BEGIN
        DECLARE @docRef VARCHAR(10), @saveDir VARCHAR(500), @TemplateID varchar(3), @letterCount int
        DECLARE @statement nvarchar(200), @EQRecordCount int
        DECLARE @ParmDefinition nvarchar(500);

        -- Get the data from table and set to variables
        SELECT @docRef = docref FROM @myTable WHERE docID = @I
        SELECT @saveDir = saveDir FROM @myTable WHERE docID = @I        
        SELECT @TemplateID = YPTMPID FROM @myTable WHERE docID = @I 

        update @myTable set actualLetters = 0 where docRef=@docRef

        create table #files (subdirectory varchar(100), depth int, [file] int)
        insert into #files  EXEC master.sys.xp_dirtree @saveDir,0,1;    

        SET @ParmDefinition = N'@EQRecordCountOUT int OUTPUT';
        set @statement= 'SELECT @EQRecordCountOUT=count(*) FROM BOCTEST.S653C36C.LIVEBOC_A.' + @docRef
        --print @statement

        execute sp_executesql @statement,@ParmDefinition, @EQRecordCountOUT=@EQRecordCount OUTPUT;
        print @EQRecordCount

        select @letterCount = COUNT(*) from #files 

        drop table #files
        update @myTable set actualLetters = @letterCount, EQRecordCount=@EQRecordCount where docRef=@docRef-- and YPTMPID=@TemplateID

        -- Increment the iterator
        SET @I = @I  + 1        
    END

select * from @myTable

所以有必要传入要填充到变量中的OUTPUT参数。

从动态SQL查询返回变量

3 个答案: