The varbinary column may contain large data such as BLOBs or images, which can take a long time to read. Try using data compression -it might help!

Thanks for the response,

You're right. restore is what really matters. Even if I omit some tables, it doesn't significantly reduce the space. So now, I feel it's better to stick...

Thanks for the reply, mate.

I try to implement that and get back to you.