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by viach 1280 days ago
> Use stored procedures

For God's sake, please don't

8 comments

Hard disagree with this attitude but I see it all the time.

Stored procedures are much faster than writing logic in some remote server (just by virtue of getting rid of all the round trips), require far less code (no DAOs, entities and all that crap which simply serves to duplicate existing definitions), and have built-in strong consistency checking primitives - which can even be safely delayed until the end of the transaction.

And what people do is, they throw all these advantages away because they can’t be bothered working out how to integrate the stored procedure code ergonomically into their workflow.

I mean - I even use an IDE (JetBrains) to write pl/pgsql. It’s just another file in my repo. Get to this point and stored procedures are a game changer.

Like you said "they can’t be bothered working out how to..." That's a fact which is not going to change.
I second that. SPs/funcs have this weird tendency to always stay hidden in the fringes and out of sight, easily forgotten when adding new functionality, easily overlooked when making changes elsewhere.
I think stored procedures can be perfectly safe provides you follow these rules:

- they live in source control

- they are covered by automated tests

- they are applied using some form of automatic database migration system (not by someone manually executing SQL against a database somewhere)

If you don't have the discipline to do these things then they are likely best avoided.

> If you don't have the discipline to do these things then they are likely best avoided.

I'd go further and say you should avoid databases and maybe even persistence entirely if you don't have the discipline to do the above. Sprocs will be the least of your problems otherwise.

Aren’t those also the absolute bare minimum bar for any code in a production system?
The realization that database procedures are code, not data, even though they reside on the database (where the data lives) is the difficult part.
That’s baffling to me. Who doesn’t realize that that thing which looks and behaves exactly like all other code isn't code?
Before the development of decent migration systems it was incredibly common for database structure - including stored procedures - to be treated independently of source code in a repository.
It's a common thing to miss. There's a reason SQL injections are (unless things have changed recently) among the most prevalent classes of web exploits.
The folks who treat databases as "that thing behind the ORM."
Yeah, I think so. But my hunch is that the majority of people who tell you never to use stored procedures have been burned by these techniques not being used for them.
Your hunch is off. We version-control DDL/DML/DQL/etc. like any other software.
"But my hunch is that the majority of people" - I'm not saying no-one does this, I'm saying I expect a lot of people don't do it.
> they live in source control

so that probably excludes 95% of legacy codebases out there from the 90s,00s

We tick all the boxes. Please contain your arrogant presumptions.
I was confused as to why you seemed to be taking offense here, then I realized that you posted the comment I was replying to.

For "you" in my comment, please read "one" instead:

> I think stored procedures can be perfectly safe provides one follows these rules:

> ...

> If one doesn't have the discipline to do these things then they are likely best avoided.

From my experience only if there are dedicated DBAs and you have too many systems running - then you forget one. If you only have server code and the stored procedures in the same repository, with migrations, this problem goes away.
I believe that stems from people frequently not including them in version control, or not doing tests.
We version-control our SPs/funcs. We have unit tests, we have integration tests.
> SPs/funcs have this weird tendency to always stay hidden in the fringes and out of sight, easily forgotten when adding new functionality, easily overlooked when making changes elsewhere.

This is the classic "carpenter blames his tools for crappy results" argument. Implementation isn't easy.

It's not. You're just making guesses.
If the developer doesn't know / doesn't document the project has code embedded in the database, that's on the developer, not the tools. Because the use of any developer tools requires a certain level of competence in order to use them successfully.
We version-control all of it. Your assumptions don't matter for reality.
Such is the life of picking complex tools
For some people I suppose
I thought so for 30 years but changed my opinion recently. I even argued with the author of Redis for some time to add some functionality so we didn't have to write Lua and have another deployment target.

Now I do think there is a benefit in stored procedures and triggers (E.g. for audits) if they don't contain too much logic or complexity.

> if they don't contain too much logic or complexity.

I think this is the catch. Most folks who are arguing against SP have been burned by huge complex stored procedures with nested dependencies with deeply intertwined business logic and rules. I completely agree that you shouldn't use a SP in that way. But to help perform maintenance, or to audit, or perform data correction all make sense when kept small and simple.

I've only given up trying to understand a system once. It was when I was handed over an application that used stored procedures for everything. Including recursive stored procedures... The rest could be figured out, but they were just too much.
I feel this. Once had something locking up a production SQL Server instance, and it turned out to be a dreadful partially-recursive web of sprocs, views, and TVFs that worked fine until apparently one day the query optimiser decided otherwise. Spent hours tracing what the heck was going on.
Why? What is your specific reasoning? Using EXPLAIN and SP's to help fix cache misses, slow queries, poor index performance, etc. is generally considered a good thing.

As a side note, I did not realize $diety was concerned about DDL/DML, so thanks for pointing it out. I never really thought about it.

Yes. Please use stored procedures. Don't listen to this guy.
Your app logic concerned with data executes somewhere, right?

So… why exactly would you exclude compute running close to the storage?

You can use that minimal latency.

Of course, people can create an uncontrolled mess of spaghetti code out of sps/funcs… like they can with any kind of code.

Stored procedures has some advantages (fast to debug/try out a query from your service without copy+paste all the time, etc), but also disadvantages (unreadable git diffs, big bang rollouts on changes)

We made this tool to get the best of both worlds:

https://github.com/vippsas/sqlcode