That would really depend on how you're retrieving the image data and how you want it to display. I guess that the Excel dump you refer to is created by exporting a text file from mySQL, which you then open in the spreadsheet - having been exported as text data, all you will get is that view in the spreadsheet.
One thing that you might need to check is that the data type of the image field in the mySQL table is set to "blob" (binary large object).
Assuming the mySQL field is set as blob data type, to retrieve the image and display in other system somehow depends on what you're doing. Having uploaded the image data to the mySQL table, are you then using it as a web server backend and want to get a php page to retrieve it and display in the browser, for example? There's a handy little snippet that shows how here:
http://www.belutz.net/2005/03/31/retrie ... using-php/
Otherwise, you will have to make a query in whatever sort of application you are creating to do the reverse of what you did in Rev to get the binary image information into the table in the first place. You could use a Rev application to query the database, and use the binary data returned to create an image, which you can then export to a file. Any other environment will require a similar process. I'm not aware of any method you could use to directly query the table with MS Excel and have the image appear in the spreadsheet - not without taking the binary data retrieved and then coding something to present it, anyway.
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