Allow the addition/query of custom columns in Blob Tables about crate

[dobe]

HI @weswam

BLOBs are addressed by their content. The primary key is the sha1 digest of the binary data it contains. This makes blobs immutable in practice. Therefore the normal use would be to store just the content in the blob table and the metadata in another table and reference the content by its sha1 hash. When the content of an object with binary data changes (e.g. a file equivalent) its digest field gets updated after the new content was uploaded to the blob table. There might be also another object with exactly the same contents ( e.g the same image is stored under different names) in which case the actual data is stored only once.

If you have a special use-case, can you elaborate on this a bit more.

regards, bernd

[weswam]

Hello @dobe

Thank you for the clarification this actually makes way more sense to me now.