[coldtea]

>If by "works well", you mean it works until someone asks for historical data - then IT guy has to say w/ a straight face "we lost it". This is unacceptable

You'd be surprised.

For tons of projects it's totally acceptable, has worked for years, nobody paying to implement them cares about historical data and their leverage. In fact the majority of web apps is like this.

I always find it strange when people use "unacceptable" with wild abandon, like they're generals receiving some demand of unconditional surrender.

[blowski]

I've probably implemented 300 CRUD projects, and I've never had a single angry person complaining about lack of access to historical data.

* I keep hourly backups of mysqldumps which can be restored in the case of catastrophic mistakes.

* I explain that this kind of data collection would be out of scope, and require significantly more budget.

Just because it's technically possible, it doesn't mean you need to do it. YAGNI.

[hcarvalhoalves]

The full sentence is:

> This is unacceptable considering the value of data and the strategic leverage it can have today.

The last part is important.

Just because it's been true in the past, it doesn't mean this trend will continue. Maybe it keeps being true for your run-of-the-mill MVP, but I don't see it being acceptable for a system in any industry w/ any chance of making serious money in the mid-term.

[blowski]

As long as managers have limited budgets and projects have deadlines, then tradeoffs will still have to be made.

Event sourcing is an extremely expensive design pattern to implement, and it's also very easy to get wrong. Implementing it tends to preclude junior developers from working on the project, makes it harder for database admins to understand the data, and it requires a lot of thought on how to structure the events.

So on a project with, say, a £20K budget, it might triple the cost. On a project that would take 4 weeks to implement with CRUD, it might take 3 months with event sourcing. You've got to justify that extra cost. It's better to let a BA decide what they will need, and by all means explain the pros and cons of different solutions.

But I don't for a second believe that every single project should now be using event sourcing instead of CRUD.

[coldtea]

>Just because it's been true in the past, it doesn't mean this trend will continue. Maybe it keeps being true for your run-of-the-mill MVP, but I don't see it being acceptable for a system in any industry w/ any chance of making serious money in the mid-term.

Again, you'd be surprised. Aside from advertising and consumer behavior analysis, there are not many industries that care or even have a need for such historical data.

The very idea that it must be necessarily valuable to store historical data about "all the things" (apart maybe from some aggregations you can create and store), seems more associated with the recent "big data" fad.

(I've seen 10-12 such trends rise and fall in the industry. In 10 years, I guarantee you it will have fallen off as a keyword, and only used as a technology where really appropriate).