You want to store an image from the Servoy media library in a db field? I am asking, because this sounds like a one time job!? If yes, this should work:
First of, ‘media:///’ is used to load any image media you have in your solution. I.e. the images that are part of your solution.
Now if you want to load an image file then you need to use the file or the image plugin to load the data of this image. You store the data into the media field.
Search the forum, there are a bunch of threads that cover that.
My intention is to add a media image at the runtime while populating data to a table. It will be much more easier if that image is in the media library.