SQLite should have (Rust-style) editions

(mort.coffee)

171 points | by gnyeki 6 hours ago ago

69 comments

  • sethev 6 hours ago

    Interesting idea - I like seeing a list of pet-peeves followed by a proposal for a straightforward way to have a set of 'alternative defaults' that remains backwards compatible. If you don't want to opt in, don't run the new PRAGMA edition = 2026.

    Too often it's just a list of issues and a wish that everyone else will change.

    In (mild) defense of SQLITE_BUSY - busy_timeout just tells sqlite to sleep and retry up to the timeout when it receives SQLITE_BUSY. It seems like a sensible default for a library to leave that up the calling code - which may have something else it could do while it waits. However, that logic often gets missed!

    • tptacek 6 hours ago

      This isn't so much a list of pet peeves as it is the almost universal way people that work seriously with SQLite configure the database. It's reasonable to suggest that the alternative settings for each of these suggestions is probably the wrong default for 2026.

      • Animats an hour ago

        > It's reasonable to suggest that the alternative settings for each of these suggestions is probably the wrong default for 2026.

        That's the key concept here. When tightening up the defaults, an "edition" mechanism is a good solution.

        Now we need this for C/C++, which have much legacy stuff which ought to go away for new code. This is more feasible than it used to be, because "Convert this Edition 4 code to Edition 5" is something LLMs can do now.

        I'd never seen all the rules for SQLite soft typing written out before. Those are more complicated than strong typing.

      • doc_ick 3 hours ago

        I’d say these are reasonable settings for most uses. Though do you know of surveys that back this up? I don’t mean to nit pick too much, I’d just like to see common uses and the data.

        • tptacek 2 hours ago

          SQLite is used in a lot of unconventional settings (for SQL databases) where these settings don't make as much sense. But that's what makes the "edition" useful; it captures the use case we all mean when we're thinking of the "database" lego in an application stack.

          • mikepurvis an hour ago

            While that's true, editions are more about leaving legacy decisions behind while keeping the backward compatibility promise.

            Even if you're in one of those unconventional settings (say, a bare-metal microcontroller or something), you'd probably still start from edition 2026 and mutate your settings accordingly, rather than using the defaults that are 26 years old.

      • sethev 6 hours ago

        Yes, agree. These are very sane defaults and match what I use..

      • pstuart 3 hours ago

        You are probably correct, but I imagine the SQLite team's dedication to backwards compatibility has things the way they are so that existing systems can user later versions a swap without worrying about changing the SQL using it.

        • usefulcat 2 hours ago

          If they’re opt-in, how could the new defaults be a problem for backwards compatibility?

        • justinsaccount 3 hours ago

          The entire point of "SQLite should have editions" is so that projects can opt into a set of modern defaults for 2026 and not get all of those backwards compatible decisions from 20 years ago.

    • mamcx 3 hours ago

      After read, it hit me that because sqlite is a DB, "editions" as-is not work.

      Because it not tied to the data but to the code.

      Instead, what I think should be is that the PRAGMAs become "data" that is always checked in full with "if manually set" and then on next "open" THEY GET APPLIED.

      That is.

      (and in the command line when open interactively they show up).

    • groundzeros2015 4 hours ago

      Yep. The whole locking database thing is this persistent myth about SQLite. All databases lock on write, it’s a question of the granularity of the lock. Multiple writers simply take turns.

      • DANmode 4 hours ago

        They don’t know by now, honestly they don’t want to know.

    • aidenn0 3 hours ago

      RE: SQLITE_BUSY: I would replace "often" with "nearly always." On top of that, it's often not fixed even when pointed out. "This software only has one writer, so we don't need to handle SQLITE_BUSY" translates to me sending SIGSTOP to a process any time I want to run some queries against its database.

  • kccqzy 6 hours ago

    SQLite is slightly different from Rust in that it is a data container. It’s somewhat more common for people to move SQLite database files from one machine to another and then inspect using the command line tool. And it is often the case that the embedded SQLite version in your app is a newer version than whatever version /usr/bin/sqlite3 happens to be. Adding editions to your SQLite file will probably break this use case of using an older version to read a database written by a newer version because it does not know what has changed in a new edition.

    Not a big deal though. Probably just need better ops to bundle the command-line utility that’s the same version as what’s used in your app.

    • tptacek 6 hours ago

      For some of these pragmas you have the same issue with or without "editions", right? Busy timeout is per-connection. And then: if you're running in WAL mode, you, the user, have to know that, or risk messing up the database by copying just the .db file rather than vacuuming-into.

      • kccqzy 6 hours ago

        Editions make the problem worse by requiring the version not only to support the underlying pragmas but also to understand the edition mapping.

        Example: PRAGMA foo=1 is introduced in 2027. PRAGMA edition=2030 implies this foo pragma. Now you unnecessarily lock out three years worth of releases.

        • tptacek 5 hours ago

          I don't see how you don't have the pragma compatibility problem either way. The edition proposal captures a bunch of behaviors that already exist.

          • kccqzy 5 hours ago

            Yes, the problem exists either way. Editions just exacerbate the problem.

    • ijustlovemath 5 hours ago

      editions could be self-describing as to certain semantic changes, and you could embed that with the file. older versions could safely ignore it and newer versions parse and run it. you could also force things like "editions must be declared early", "editions are one way only" etc to get some level of security in the adoption of the change

    • arijun 5 hours ago

      I think you can maintain full backward compatibility with all these changes. SQLite has a bunch of meta-data that you can use to see that no earlier editions have modified your database since you last wrote. You make the new editions follow these strict rules, but if an old edition modifies the DB in the interim, you fall back to the original rules, until it’s verified compliant again.

    • appplication 6 hours ago

      It seems SQLite could be evolve to solve this by just bundling itself entirely in the data files? After all, the binary is less than 1MB, anywhere you’re putting a database surely has at least that much overhead, for most applications it’s less than a drop in the bucket.

      I’d be interested to learn if there are any db implementations that take this approach, or reasons this wouldn’t work.

      • mort96 5 hours ago

        Well you'd have the problem that an sqlite database file created on a Linux AMD64 box could be copied to an AArch64 macOS machine to be read there. And quite a lot of (cross platform) software build their file formats on top of SQLite.

        • appplication 5 hours ago

          I think my silly and unserious naive response would be linear scaling bundled binaries with number of platforms doesn’t seem to be that materially different in terms of total size. But I see your point, didn’t consider the architectures

        • andai 5 hours ago

          Perhaps it could be an "actually portable executable"?

          https://news.ycombinator.com/item?id=26273960

      • arijun 5 hours ago

        So for every new SQLite db you want to access would have to run a new untrusted executable? That seems… hilariously bad for security.

        • appplication 5 hours ago

          Fair point! Was mostly an intrusive technical thought

    • Rendello 5 hours ago

      > SQLite is slightly different from Rust in that it is a data container.

      I think this is the key.

      From sqlite.org [1]:

      > [Since 2004], the file format has been fully backwards compatible.

      > By "backwards compatible" we mean that newer versions of SQLite can always read and write database files created by older versions of SQLite. It is often also the case that SQLite is "forwards compatible", that older versions of SQLite can read and write database files created by newer versions of SQLite. But there are sometimes forward compatibility breaks. Sometimes new features are added to the file format

      ---

      Given editions (A) and (B), what does backwards compatibility look like? Must (B) be backwards compatible with (A)?

      If yes -> editions are backwards compatible but not necessarily forwards compatible, which is the current status quo:

          -------(A)----(B)--
      
      If no -> editions are not backwards compatible, the edition space is bifurcated:

          ---+----(A)--------
              \
               \--(B)--------
      
      Now you may have to worry about backwards compatibility with (A)..(Z). What happens when you import a file from edition (Y)?

      1. https://www.sqlite.org/formatchng.html

      ---

      Interesting PS, grepping sqlite.org for "backwards compat": https://pastebin.com/Q7b7h4eM

      • mort96 5 hours ago

        The answer to the question "What happens when you import a file from edition (Y)" should, ideally, be exactly the same as the answer to the question "What happens when you import a file created with parameters foo, bar and baz set to values a, b and c". There's really nothing new here.

        Some parameters are properties of the database file itself, such as (I believe) journal_mode. These parameters probably result in issues with earlier versions of sqlite; if you create a file with journal_mode WAL, you're not gonna be able to open it in a version of sqlite without WAL support. Same with strict tables; if you have a database which contains strict tables, I assume you're going to encounter issues if you try to open it in a version of sqlite too old to support strict tables. But anything new enough to support the individual database file features shouldn't have any trouble. This is true whether we're talking about an edition pragma or individual parameters set the old way.

        Some parameters are properties of the connection, like the foreign_keys parameter. If you're trying to open a database file in a version of sqlite which doesn't support foreign key validation at all, just don't set the foreign_keys parameter.

  • andai 5 hours ago

    The "use strict" thing is interesting. I often hear people say, well we can't fix absurd behavior in JS because backwards compatibility! Well, we already did, and we can do it again!

  • mort96 6 hours ago

    Oh hi, author here. Fun to see this make it to HN.

    • rmunn 3 hours ago

      Found what appears to be a minor mistake you may want to fix: "This means that a dangling reference easily results in a reference to the wrong column" should probably be "... a reference to the wrong row". (In the paragraph about SQLite's tendency to re-use ROWIDs).

      • mort96 36 minutes ago

        You're right, thanks. Fixed

    • simonw 6 hours ago

      Suggestion: post this on https://sqlite.org/forum/forum - the SQLite team monitor that forum closely and I've had some really great answers from them to questions or suggestions in the past.

      • mort96 6 hours ago

        I haven't really ever participated in that forum before, but it's an interesting idea. I don't know if I'm going to do it, I might. Though I also wouldn't mind if someone else posted about it there. I might even make a forum account and participate in the discussion.

      • quadhome 6 hours ago
  • Retr0id 3 hours ago

    An alternative is to use wrapper libraries that set sane defaults, e.g. https://rogerbinns.github.io/apsw/bestpractice.html

    But I suppose it would be nice to have a standard way to refer to those defaults, in a cross-runtime way.

  • andai 5 hours ago

    In the first example, there's a a second thing that surprised me: you delete an entity and it's unique ID gets reused? Is that a good idea?

    I guess if foreign keys are handled properly then that's not a problem by definition? But it sounds wrong somehow.

    • deepsun 4 hours ago

      I think that's a security vulnerability.

      If a parent table ID gets reused, then it's a potential to expose data to a wrong user -- security broked.

    • bruce511 2 hours ago

      >> you delete an entity and it's unique ID gets reused? Is that a good idea?

      That's default behavior, but it can be altered when creating a table. See;

      https://sqlite.org/autoinc.html

  • souvlakee 5 hours ago

    Sadly, the ORM layer lags here: Drizzle has no way to declare STRICT tables. The request has been open since March 2023 (issue #202, now discussion #2435) and didn't make the v1.0 beta either. The only workaround is hand-appending STRICT to generated migration SQL, which doesn't work at all if you use `drizzle-kit push`.

    https://github.com/drizzle-team/drizzle-orm/discussions/2435

  • tmpfile 2 hours ago

    Why not a .conf file like everything in /etc or postgresql.conf?

    • hmry an hour ago

      These proposed editions are per connection.

      A system-wide config file in /etc that changes defaults for every program would break any program that assumes the old defaults.

      It also wouldn't solve the problem of having to manually find out what the current recommended defaults are. With editions, you can simply enable the latest one and know you've got the right defaults.

      • tmpfile 21 minutes ago

        I should have been more clear, I meant a sqlite.conf can configure a program rather than have it apply globally. For example, a config file placed in same directory as its .wal file to tune it for specific instances. That way you don’t need to lookup what “editions” apply which pragmas or settings. With sqlite.conf you can tune your specific database connections by uncommenting the default settings to enable current features/best practices

  • andrewchambers 3 hours ago

    It is sqlite3. Emphasis on the 3 - it already has 'editions'.

  • Rendello 6 hours ago

    It might be worth bringing this up on the forum [1]. The developers are quite active there, and it's possible they've never considered this option, or they have considered it and have reasons to not go for it. The original design followed Postel's Law (see my comment from the other say [2]), it would (theoretically) be nice if that mess could be avoided by specifying an edition.

    Today I noticed I could do `pragma foreign_key = ON`, and despite the pragma being wrong (it should be foreign_keys, plural), it reported nothing. In fact, it reports nothing with the correct pragma either. So check your pragmas!

    1. https://sqlite.org/forum/forum

    2. https://news.ycombinator.com/item?id=48900625

  • GianFabien 3 hours ago

    Nah, all those defaults are features. Of course, there are contexts where those defaults are unsuitable which means: Use a Different RDBMS!

    • Rohansi 3 hours ago

      Change RDBMS instead of changing configs from their default value? They're configurable for a reason.

    • Cyberdog an hour ago

      Are there any other serverless SQL DBMSes?

  • chillfox 4 hours ago

    you can also set those defaults with compile time flags, that's what I have been doing.

  • eduction 3 hours ago

    HN… for the love of god… please please stop trying to make SQLite be something it isn’t. Leave this poor project alone.

    It’s a great tool if you want to give a local app its own database. If you need concurrent writes and full ACID guarantees of an industrial strength database, use an industrial strength database.

    Yes, other databases will require you to read more manual pages and configure a service. Higher up front cost. Not “lightweight.” But given enough operating time there is a certain unarguable lightness to using the right tool for the job.

    • yomismoaqui 2 hours ago

      Just by its testing and its number of installations (real world testing) you could consider SQLite being more "industrial strength" than any other DB on the market.

      - https://sqlite.org/testing.html

      - https://sqlite.org/mostdeployed.html

      EDIT: added links

      • eduction an hour ago

        Exactly. There is no reason to complain about it. It is successful. People who find it lacking can use something else, there are many options.

    • Cyberdog an hour ago

      I don’t understand why a local app database shouldn’t still have the same basic functionality and data guarantees as the full-sized ones.

  • Thaxll 5 hours ago

    SQLite gets so much praise here but when you start using it, you realize quickly how bad it is, the type system is by default very limited and dangerous.

    It's like comparing old php with a strongly typed language.

    There is not even a date type...

    • groundzeros2015 4 hours ago

      SQLite competes with fopen. Not Postgres

      • wang_li 4 hours ago

        It’s curious how many people don’t understand what SQLite is and its intended feature set. They get huffy that it’s not a full client server model with multimaster clustering across 8 data centers on 12 continents plus New Zealand with realtime synchronous replication.

        It’s a product that allows you to do sql like things without a database server. If you need to have database server behavior, you’re using the wrong product.

        • lbourdages 3 hours ago

          Well, it goes both ways. You'll see articles saying essentially "you don't need Postgres or any other fancy database, SQlite is enough" while ignoring the fact that some use-cases warrant a more conventional DB server.

          Different tools for different situations!

    • kccqzy 4 hours ago

      It’s not as bad since you can always use a powerful programming language with a good type system that avoids type errors at the SQL level. You can build good abstractions in your programming language.