sp_send_dbmail将存储为varbinary的文件附加到数据库中

Question

我有两个问题涉及使用sp_send_dbmail将查询结果作为附件发送.

问题1:只打开基本的.txt文件.任何其他格式如.pdf或.jpg都已损坏.

问题2:尝试发送多个附件时,我会收到一个文件,其中所有文件名都粘在一起.

我正在运行SQL Server 2005,我有一个存储上传文档的表:

CREATE TABLE [dbo].[EmailAttachment](
[EmailAttachmentID] [int] IDENTITY(1,1) NOT NULL,
[MassEmailID] [int] NULL, -- foreign key
[FileData] [varbinary](max) NOT NULL,
[FileName] [varchar](100) NOT NULL,
[MimeType] [varchar](100) NOT NULL

我还有一个带有标准电子邮件的MassEmail表.这是SQL Send Mail脚本.为简洁起见,我排除了声明声明.

while ( (select count(MassEmailID) from MassEmail where status = 20 )>0) 
begin
    select @MassEmailID = Min(MassEmailID) from MassEmail where status = 20
    select @Subject = [Subject] from MassEmail where MassEmailID = @MassEmailID
    select @Body = Body from MassEmail where MassEmailID = @MassEmailID

    set @query = 'set nocount on; select cast(FileData as varchar(max)) from Mydatabase.dbo.EmailAttachment where MassEmailID = '+ CAST(@MassEmailID as varchar(100))  

    select  @filename = ''
    select  @filename = COALESCE(@filename+ ',', '') +FileName from EmailAttachment where MassEmailID = @MassEmailID

exec msdb.dbo.sp_send_dbmail    
    @profile_name = 'MASS_EMAIL',
    @recipients = 'me@myemail.com',
    @subject = @Subject,
    @body =@Body,
    @body_format ='HTML',
    @query = @query,
    @query_attachment_filename = @filename,
    @attach_query_result_as_file = 1,
    @query_result_separator = '; ',
    @query_no_truncate = 1,
    @query_result_header = 0;

update MassEmailset status= 30,SendDate = GetDate() where MassEmailID = @MassEmailID
end   

我能够成功读取数据库中的文件,因此我知道二进制数据没有损坏.

.txt文件仅在我将FilaData转换为varchar时读取.但显然原始标题丢失了.值得注意的是,附件文件大小与原始文件不同.这很可能也是由于编码不当造成的.所以我希望有一种方法可以使用存储的mimetype创建文件头,或者某种方式在二进制数据中包含文件头？

我对最后几个参数的值也没有信心,我知道coalesce不太正确,因为它用逗号预先设置了第一个文件名.但是几乎不可能找到好的文档.请帮忙!

Answer 1

我不认为你能直接从SQL发送二进制数据.有一些帖子谈论同样的问题.从Microsoft文档中,将返回查询的文本格式化为文本文件.二进制格式为十六进制.正如您所指出的那样,破坏了任何非文本文档的文件.

我认为你仍然可以完成你想要做的事情,但首先使用BCP将二进制数据导出到文件系统,然后通过sendmail可用的传统文件附件方法将其导入.

所以这样的事情.(仅限概念 - 未经测试的代码)

DECLARE @OutputFileAndPath VarChar(500) = '\\Log_Files\MyFile.pdf ' 
DECLARE @sql VarChar(8000)

SELECT @sql = 'BCP "SELECT MyFile FROM [dbo].[MyTable] 
    WHERE PrimaryKey = 12345" queryout ' + @OutputFileAndPath +
        ' -S MyServer\MyInstance -T -fC:\Documents.fmt'

/* you could use a generic format file that would cover most formats */

EXEC xp_cmdshell @sql, NO_OUTPUT;

while ( (select count(MassEmailID) from MassEmail where status = 20 )>0) 
begin
    select @MassEmailID = Min(MassEmailID) from MassEmail where status = 20
    select @Subject = [Subject] from MassEmail where MassEmailID = @MassEmailID
    select @Body = Body from MassEmail where MassEmailID = @MassEmailID


    exec msdb.dbo.sp_send_dbmail    
        @profile_name = 'MASS_EMAIL',
        @recipients = 'me@myemail.com',
        @subject = @Subject,
        @body =@Body,
        @body_format ='HTML',
        @file_attachments = @OutputFileAndPath /* i.e. \\Log_Files\MyFile.pdf */

    update MassEmailset status= 30,SendDate = GetDate() where MassEmailID = @MassEmailID
end