See: https://atlasgo.io/concepts/declarative-vs-versioned#combini..., and https://github.com/ariga/atlas-action?tab=readme-ov-file#ari...
I built this last summer and thought it was fairly complete. And it turns out I was naive. 6 months later, I have resolved ~100 issues reported by the users.
Also means I can stop with my hobby project that was supposed to do the same. Wasn't far along and haven't worked on it in months anyway.
So I'll spend my time on another hobby project then that also solves something that is already solved 100 times over, but I don't like the other solutions (simple log monitoring including systemd and sending error emails if something is found).
https://david.rothlis.net/declarative-schema-migration-for-s...
i like the following about it 1. database schema is regular code 2. make schema change declaratively 3. packaging (.daspac) and deployement script
most open source tools , seem to be after the fact tools, that do diffs ms db project, handle the code from the start in a declarative, source code managed way
Isn't it much quicker to write a one line migration vs copying the DDL, then adapting it to the desired state and then getting getting the migrations from that tool? Or am I misunderstanding something?
In the big picture, declarative schema management has lots of advantages around avoiding/solving schema drift, either between environments (staging vs prod) or between shards in a sharded setup (among thousands of shards, one had a master failure at an inopportune time).
It's also much more readable to have the "end state" in your repo at all times, rather than a sequence of ALTERs.
There are a bunch of other advantages; I have an old post about this topic here: https://www.skeema.io/blog/2019/01/18/declarative/
It's also quite essential when maintaining nontrivial stored procedures. Doing that with imperative migrations is a gateway to hell. https://www.skeema.io/blog/2023/10/24/stored-proc-deployment...
Schema management is only a small part of the problem, and I don’t think this tool handles data migrations. E.g. if I reshape a JSONB column into something more structured, I don’t think it would be able to handle that. Or if I drop a column the backwards migration it generates ADD COLUMN … NOT NULL, which is obviously unusable if the table has any data in it already.
sqldef is really cool for supporting many database dialects. I'm the author of Skeema [1] which includes a lot of functionality that sqldef lacks, but at the cost of being 100% MySQL/MariaDB-specific. Some other DB-specific options in this space include Stripe's pg-schema-diff [2], results [3], stb-tester's migrator for sqlite [4], among many others over the years.
The more comprehensive solutions from ByteBase, Atlas, Liquibase, etc tend to support multiple databases and multiple paradigms.
And then over in Typescript ORM world, the migrators in Prisma and Drizzle support a "db push" declarative concept. (fwiw, I originated that paradigm; Prisma directly copied several aspects of `skeema push`, and then Drizzle copied Prisma. But ironically, if I ever complete my early-stage next-gen tool, it uses a different deployment paradigm.)
[1] https://github.com/skeema/skeema/
[2] https://github.com/stripe/pg-schema-diff
[3] https://github.com/djrobstep/results
[4] https://david.rothlis.net/declarative-schema-migration-for-s...
1. DB is source of truth, generate TS from DB 2. TS to DB direct sync, no migration files 3. TS source, Drizzle generates and applies SQL 4. TS source, Drizzle generates SQL, runtime application 5. TS source, Drizzle generates SQL, manual application 6. TS source, Drizzle outputs SQL, Atlas application
Personally I've called it a mistake, since there's no way a tool can infer what happened based on that information.
That might sound like a major caveat, but many companies either ban renames or have a special "out-of-band" process for them anyway, once a table is being used in production. This is necessary because renames have substantial deploy-order complexity, i.e. you cannot make the schema change at the same exact instant as the corresponding application change, and the vast majority of ORMs don't provide anything to make this sane.
In any case, many thousands of companies use declarative schema management. Some of the largest companies on earth use it. It is known to work, and when engineered properly, it definitely improves development velocity.