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Comment by kasey_junk | Hacker News Reader

The article describes why. 2 different db engines (or even instances) can use different file layouts for the same schema.

In many was sql is all about divorcing the schema from the files.

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But on the other hand, in all database systems the schema is used to determine how the files are laid out. Although I suppose the same thing could be argued for any data that is stored in a file, excepting that a schema is metadata that determines the organisation of data so it's a bit of a special case.

In a Microsoft Word document, the section headings also tell Word how to lay out the Word document file.

Do you mean that section headings aren't a file layout? That's their entire purpose.

Edit: If you're talking about the byte representation only, I don't think section headings indicate the placement of the body's bytes.

You have found an argument that proves too much.

Yea coupled with the courts arguments the interpretation of sections in a document as a "file format" means no files with sections can be released via FOIA requests

Does your interpretation not mean that(coupled with the court ruling that file formats can't be foia'd) any document with sections cannot be requested via FOIA?

If this format is reused across many files, they might want to give the contents of those docs in a different format from the original.

Arguably, all requests for files could be returned with all of the letters in the document but scrambled in a random order soas to obfuscate the file layout.

There's a solid chance that the schema gives away what DBMS is being used. But even if it didn't, I'd still call it a file layout in this context.

So?

So if you have the schema and the DBMS, you probably know how data is arranged in the files ("files" in the filesystem sense).

The parent asks "how is it not a file layout" not "can you guess the file layout?" given it.

I am a human, you know I have a kidney, but I am not a kidney.

If you send a copy of the code, is that sending the code? If it is, what about sending a copy of the code with a Caesar Shift?

Is your argument that government agencies should also withhold the names of filing cabinet manufacturers? :)

Just that it's a file layout. Or even if you strictly define a file layout as say an ext4, NTFS, or FAT file tree, that revealing the schema is revealing the file layout.

I don't know why they don't want to reveal file layouts, but for whatever reason, they decided it was "per se" exempt regardless of the security implications.

It's obviously not a file format. The same SQL schema can generate N different files, with N different layouts, for N different databases. By the logic you're using ("schema" + "database vendor" = "file format"), a Word document outline is also a file format.

The DBMS is almost definitely going to be mentioned in RFP or specification documentation. As it was in this lawsuit.

The gov't releasing the hardware and software licencing used in CANVAS already gives that away.

Another way to think about it is that if a SQL schema is a file, so is an Excel spreadsheet template.

File or file layout? Cause both of these are probably stored as files, .sql and .xltx respectively.

An Excel spreadsheet template is an arrangement of rows/columns/cells which is encoded in a XML document which is encoded in a ZIP file archive.

I don't follow your point.

Yes, it's a file format.

(Kinda a file format inside a file format inside a file format.)

"Excel" is a file format, but my point is that if a schema is a file format, so are the contents of an Excel spreadsheet.

It's interesting that the opening analogy in the post uses an Excel spreadsheet as a great way to explain a database. It's such an easy next step to say the way an xls/ods file is saved is a file format but the column layout in the tabs/tables are the schemas. The court (and the city) playing these games is so scary since it is so biased toward all modern government data being covered by FOIA exemptions.

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