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Comment by mulmboy | Hacker News Reader

As a counterpoint I find that nutting out the schema upfront is an incredibly helpful process to define the functionality of the app. Once you have a strict schema that models the application well nearly everything else just falls into place. Strong foundation

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I worked at a startup who did the whole "every table schema is "id, data" where data is a JSON blob with all the data." I loved it at first. For initial development, it felt so freeing and so productive.

Then one of the devs left and I inherited his code, and started to realize exactly how much the rigid schema helps make an app more robust and more maintainable. I will never, ever take that shortcut again. The production outages/downtime caused by database issues that never should have been an issue in the first place (like a corner case row that missing data? Spreading rampant defensive nil checks out across every function that checks any field of a record since any at any time might be inconsistent or nil) contributed to killing the company by pissing off customers.

Elixir/Phoenix does help a lot though because I still treat most rows like JSON objects, but under the hood it's a normal rigid postgres schema. Best of both worlds IMHO.

With JSON blobs in simple tables a very large part of designing a database schema becomes designing a JSON schema, with different opportunities to make mistakes but (potentially) the same strictness.

How do you enforce the JSON schema?

We are talking about the internal database of some application: its schema is something that should be designed well, not enforced defensively like a schema for validating undependable inputs.

define schema with data class and you have tools like protobuf/thrift. And I find it really unnecessary to map every attribute to a SQL column.

In the application layer

Nutting?

https://www.macmillandictionary.com/us/dictionary/american/n...

https://idioms.thefreedictionary.com/nutting+out

Thinking. British English idiom. Using your nut - your head.

Tends to mean "ejaculating" in American English, for the record.

What's the difference?

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