Would there be any performance issue with reading the BLOB (which might be 10 megabytes in size or more) into the same hash that contains the related metadata?

This depends entirely on how much physical and virtual memory you have available, how other applications are competing for that memory, how the OS responds to competing demands, and how fast your disks are (since you'll swap quicker with faster disks). Do note that any operation on that blob that will require a temporary copy will double your RAM hit.

There's no problem per se with sticking a hugh object into a hash.

In reply to Re: Storing a BLOB in a Hash by dws
in thread Storing a BLOB in a Hash by Wally Hartshorn

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