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0 pointsawesome_dude9mo ago0 comments

> Perhaps, if the C# applications are the only ones accessing the database. But suppose multiple applications written in different languages (and for different purposes) need the database access?

Without wishing this to sound like a personal attack, YUCK

A database that's accessed by multiple applications, regardless of the number of languages, is a really bad smell.

If I have a user db, and hundreds of other applications want to make use of the data in it, they come through MY application. I own the db, I decide what's in it, how the data is shaped, and when it changes.

Multiple applications accessing a single database is asking for a bureaucratic nightmare - "App A wants to change the first name field to UTF-8" - EVERY other user, of that database needs to be informed (best of luck figuring out what other apps are, and who owns them). If you are tempted to say "Those other apps should support UTF-8 as well" then that's the sound of someone that's never had legacy code in the environment.

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henrikschroder9mo ago

> A database that's accessed by multiple applications, regardless of the number of languages, is a really bad smell.

Except that really was the original model back in the 90's. All "good" databases had an extensive roles and permissions system, and a point of pride was the number of ODBC connectors for different languages and environments.

You were supposed to have The Database, looked after and controlled by the hallowed DBAs, who had their own hardware budget, their own organization, and who controlled access to The Database, giving trusted applications access to it, but only after they had vetted the schema and queries that those dirty developers wanted to run against it. Trusted users could get SELECT access, but only to the tables they needed to run their custom reports and queries.

It was a whole ass thing that's fallen completely to the wayside as database software went from underpinning Larry's latest mega-yacht, to free as in beer, and we learned how to clone and shard the data instead.

xyzzy1239mo ago

Now we write graphql adapters over dozens of microservices to get back the capability to express queries and lessen the burden of hardcoding every possible query for frontend. N+1 is just more fun at the party and with a bit of effort you can make basic queries depend on the health of almost every service in your infrastructure.

If you squint at it wrong, it looks like some kind of bizarre and inhumane jobs program.

Meanwhile, transactions remain forgotten lore. Simply not achievable at our current tech level.

mike_hearn9mo ago

It's not much different. If you have a bunch of API clients that don't agree on character encodings you'll have a tricky migration process too.

LorenPechtel9mo ago

The important part is what changes it.

Read my files, fine. I always try to avoid breaking changes anyway. Just don't write them!!

zabzonk9mo ago

Precisely why I said the applications should access the data via a server process - they never know the underlying database schema.

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