如何将图像字段导出到文件？

Question

我正在使用Microsoft SQL Server Management Studio连接到数据库.在其中我有一个表,其中一列是包含文件数据的Image列.另一列是包含文件名的字符串.

有什么方法可以编写一些sql脚本,允许我选择一条记录并将这些数据写入文件？或者,如果这不可能,那么实现这一目标的简单方法是什么？

我已经看到了这个相关的问题,但它看起来并不完全相同:在sql-server 2000中将图像列保存到文件中

Answer 1

-- Write all database images (jpg) to file.
--------- --------- --------- --------- --------- --------- --------- 
DECLARE CURSOR_ProductIds CURSOR FOR (SELECT ImgImagesId FROM ImgProductSample)

DECLARE @ProductId INT;

OPEN CURSOR_ProductIds

FETCH NEXT FROM CURSOR_ProductIds INTO @ProductId
WHILE (@@FETCH_STATUS <> -1)
BEGIN
  DECLARE @ImageData varbinary(max);
  SELECT @ImageData = (SELECT convert(varbinary(max), ImageData, 1) FROM ProductImages WHERE Id = @ProductId);

  DECLARE @Path nvarchar(1024);
  SELECT @Path = 'C:\MyImages\Output';

  DECLARE @Filename NVARCHAR(1024);
  SELECT @Filename = (SELECT ImageFilename FROM ProductImages WHERE id = @ProductId);

  DECLARE @FullPathToOutputFile NVARCHAR(2048);
  SELECT @FullPathToOutputFile = @Path + '\' + @Filename;

  DECLARE @ObjectToken INT
  EXEC sp_OACreate 'ADODB.Stream', @ObjectToken OUTPUT;
  EXEC sp_OASetProperty @ObjectToken, 'Type', 1;
  EXEC sp_OAMethod @ObjectToken, 'Open';
  EXEC sp_OAMethod @ObjectToken, 'Write', NULL, @ImageData;
  EXEC sp_OAMethod @ObjectToken, 'SaveToFile', NULL, @FullPathToOutputFile, 2;
  EXEC sp_OAMethod @ObjectToken, 'Close';
  EXEC sp_OADestroy @ObjectToken;

  FETCH NEXT FROM CURSOR_ProductIds INTO @ProductId
END
CLOSE CURSOR_ProductIds
DEALLOCATE CURSOR_ProductIds

-- Make sure the following statement is executed to enable file IO
-- From http://msdn.microsoft.com/en-us/library/ms191188.aspx
--------- --------- --------- --------- --------- --------- --------- 
sp_configure 'show advanced options', 1;
GO
RECONFIGURE;
GO
sp_configure 'Ole Automation Procedures', 1;
GO
RECONFIGURE;
GO

Answer 2

来自codeproject的mkader:

EXEC sp_configure 'show advanced options', 1;  
GO  
RECONFIGURE;  
GO
EXEC sp_configure 'xp_cmdshell',1  
GO  
RECONFIGURE;  
GO

然后转储格式文件:

Declare @sql varchar(500)
SET @sql = 'bcp DBName.dbo.tblTableName format nul -T -n -f C:\testblob.fmt -S ' + @@SERVERNAME
select @sql 
EXEC master.dbo.xp_CmdShell @sql 

我的格式文件如下所示:

10.0
12
1       SQLINT              0       4       ""   1     my_tablecol_id                                  ""
2       SQLINT              1       4       ""   2     my_tablecol0                                   ""
3       SQLCHAR             2       256     ""   3     my_tablecol1                                SQL_Latin1_General_CP1_CI_AS
4       SQLCHAR             2       256     ""   4     my_tablecol2                                SQL_Latin1_General_CP1_CI_AS
5       SQLCHAR             2       256     ""   5     my_tablecol3                         SQL_Latin1_General_CP1_CI_AS
6       SQLCHAR             2       2048    ""   6     my_tablecol4                                SQL_Latin1_General_CP1_CI_AS
7       SQLIMAGE            4       0       ""   7     my_imagecol                                     ""
8       SQLCHAR             2       2048    ""   8     my_tablecol6                            SQL_Latin1_General_CP1_CI_AS
9       SQLINT              1       4       ""   9     my_tablecol7                                      ""
10      SQLINT              1       4       ""   10    my_tablecol8                                    ""
11      SQLINT              1       4       ""   11    my_tablecol9                               ""
12      SQLBIT              1       1       ""   12    my_tablecol10                             ""

然后,我编辑了格式文件,如下所示:

10.0
1
1       SQLIMAGE            0       0       ""   1     my_imagecol                                     ""

然后在SSMS中运行此SQL:

Declare @mynum int
Declare @sql varchar(500)
SET @mynum = 49 -- something meaningful only to me
SET @sql = 'BCP "SELECT my_imagecol FROM DBName.dbo.tblTableName where my_tablecol_id=@mynum" QUERYOUT C:\myfilename.docx -T -fC:\testblob.fmt -S ' + @@SERVERNAME
EXEC master.dbo.xp_CmdShell @sql

这非常有效,图像列中的任何类型的数据都可以工作.