Ability of an ISBN search of my collection would have helped me in this case - scanning a barcode is easy enough task to accomplish.
And even if I had a different edition, the resulting title from searching for a different edition would be enough to help me figure out that I should not buy a book I already own.
Sometimes these have different catalogue numbers or barcodes to distinguish them, sometimes they don't but they're still different. I've seen releases where the only difference is the label in the centre of the LP, or the back of the CD case has a two-column tracklisting vs a one-column tracklisting. Music publisher uses the same code and says it's identical and yet it's clearly not.
Then there's the "recordings" on an album, which even if they're never re-recorded can still end up chopped up, bleeped or remastered. They're not the same sound. MusicBrainz likes to track when they are exactly the same recording (e.g. the LP recording of a song appearing on a compilation album verbatim) and when they're not (e.g. radio edits of the LP recording). And if we're going beyond recordings by one artist of "their" song, i.e. cover versions, or just plain standards, those are "works", with composers, lyricists, and can be recorded thousands of times by different artists...
I greatly appreciate the pedantry and flexibility for noting down when creative works are the same versus where they differ, in relational database form.
[0] https://musicbrainz.org/release-group/1b022e01-4da6-387b-865...
I haven't looked into what their schema is like, but if it's anything like Musicbrainz it will be pretty comprehensive and easy to pull the data you want out of!
For example, compare the most recent edition of 'Straight and crooked thinking' with the one published in 1930.
I "grew up with" a specific translation of Lord of the Rings into Norwegian, for example. There are two. They are very different. But the editions also differ in whether they include the appendices, whose illustrations are used, and more.
[0] Before anyone says it, I'm sure some bible nerd has numbered them, it's hyperbole.
However, within the block publishers can assign ISBNs to different imprints.
I worked on the library systems and one of my innovations was to use the ISBN mapping database of WorldCat to find books with identical content but different ISBNs to help kids find the books on the list.
Over ten years that one SQL join in the code made the kids read an extra million books they wouldn’t have otherwise.
My biggest “bang for buck” in my career!
tl;dr; - The ISBN is intended to be a physical Part Number, within the book business. Where "hardcover, or paperback, or trade paperback, or large print, or revised edition, or ..." very much matters.