使用游标

Question

我无法理解我的错误在哪里。

我正在尝试遍历表并将以image数据类型存储的PDF文件传送到特定位置。

我写了光标，但它在'+'

旁边给了我一个语法错误

CREATE TABLE #tblPolicyForms
(
    FormID INT NOT NULL,
    PDF VARBINARY(MAX) NULL,
    PDF_FIlename VARCHAR(MAX)
)

INSERT INTO #tblPolicyForms
    SELECT  
        FormID, PDF, PDF_FileName
    FROM    
        [dbo].[tblPolicyForms]
    WHERE   
        FormID IN (19, 20, 21, 22)

--select * from #tblPolicyForms

DECLARE @FormID varchar(4);
DECLARE @FileName VARCHAR(200);

DECLARE FormID_cursor CURSOR FOR 
    SELECT
        FormID, PDF_FIlename
    FROM
        #tblPolicyForms
    WHERE 
        FormID IN (19, 20, 21, 22)
    --where whatever conditions you need to get the FormIDs you want to use

OPEN FormID_cursor

FETCH NEXT FROM FormID_cursor INTO @FormID, @FileName

WHILE @@FETCH_STATUS = 0
BEGIN
    EXEC master.dbo.xp_cmdshell 'BCP "SELECT PDF FROM [MEJAMES].[dbo].tblPolicyForms " queryout "C:\Users\oserdyuk\Documents\ExportDir\'+@FileName+'" -T -N'

    FETCH NEXT FROM FormID_cursor INTO @FormID, @FileName
END

CLOSE FormID_cursor
DEALLOCATE FormID_cursor

Answer 1

使用变量：

DECLARE @cmd NVARCHAR(MAX) = N'BCP "SELECT PDF FROM [MEJAMES].[dbo].tblPolicyForms " queryout "C:\Users\oserdyuk\Documents\ExportDir\'+@FileName+'" -T -N';

EXEC master.dbo.xp_cmdshell @cmd;

来自文档EXEC：

  

{值
                             | @variable [OUTPUT]
                             | [默认]
                             }

所以你只能传递值（文字），变量或默认值。在您使用+的示例中，您试图传递导致错误的表达式。

注意：最好以分号结束每个语句。