Is it possible to write out images from SQL Server to a mapped drive?

Question

I am using a cursor to write out images stored in a database to text.

Code snippet here:

DECLARE @SOURCEPATH VARBINARY(MAX),
        @DESTPATH VARCHAR(MAX),
        @ext varchar(MAX),
        @ObjectToken INT,
        @image_ID Varchar(255)

DECLARE IMGPATH CURSOR FAST_FORWARD FOR
    SELECT <my data>
    FROM <my table>

OPEN IMGPATH

FETCH NEXT FROM IMGPATH INTO @SOURCEPATH, @image_ID

WHILE @@FETCH_STATUS = 0
BEGIN
    SET @DESTPATH = '<my path>'+ @image_ID  

    EXEC sp_OACreate 'ADODB.Stream', @ObjectToken OUTPUT
    EXEC sp_OASetProperty @ObjectToken, 'Type', 1
    EXEC sp_OAMethod @ObjectToken, 'Open'
    EXEC sp_OAMethod @ObjectToken, 'Write', NULL, @SOURCEPATH
    EXEC sp_OAMethod @ObjectToken, 'SaveToFile', NULL, @DESTPATH, 2
    EXEC sp_OAMethod @ObjectToken, 'Close'
    EXEC sp_OADestroy @ObjectToken

    FETCH NEXT FROM IMGPATH INTO @SOURCEPATH, @image_ID
END

CLOSE IMGPATH
DEALLOCATE IMGPATH

I am able to write to a local drive without a problem, but I cannot write to the network share that I'd like to write to. I've followed the steps here,

https://www.mssqltips.com/sqlservertip/3499/make-network-path-visible-for-sql-server-backup-and-restore-in-ssms/

in an effort to make the drive "visible" to SQL Server, but I still am not having any luck writing the images to this mapped drive.

Is this functionality supported, should I go down the route of checking permissions with our network guys, or is this not something that is possible?

Answer 1

SQL Server can usually see a UNC path like \\server\share\subfolder

But only if the service running SQL Server has rights to that share. For example, if you're running a scheduled job, the job runs as the user for the SQL Agent Service. If you're running code directly in SSMS or a stored procedure called from your program, then the SQL Engine Service must have rights to that shared folder.

If that user is a local user only, then it won't have rights to the shared folder. SQL Server engine and/or agent must be running as a domain user to access the volume.

For example, we run our backups to a \\server\DBs\SQL\<server name> shared drive. The SQL Agent Service account has to have full rights to that shared folder for the backups to succeed. There's no mapped drive involved in these backups.