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by progmetaldev 632 days ago
I have upvoted you for each comment you've made, but I feel like it's not that simple. Even just getting a single vendor to implement it is a huge undertaking. I know that you and I see the value in it, but I don't feel like we're the first to see that. There's a reason behind not implementing this feature, and it's the complexity that lies behind such a feature, like most things. This seems like one of those recursive and interactive features that don't fit into SQL. Does it present the rows that will be updated or deleted, and then ask if you wish to perform the operation? That doesn't work like anything SQL based, and I feel that's why we don't have it. I appreciate the back and forth on this, and am curious as to how you think it should be handled, if there's a way to fit in the way SQL works.
2 comments
kristopolous 632 days ago
If the expectation is not met then it rolls back and fails. I implemented a slipshod version of it years ago for a previous employer (it got the job done with a lousier syntax)

Here's a list of 1,000 postgres extensions, it's not a big deal: https://gist.github.com/joelonsql/e5aa27f8cc9bd22b8999b7de8a...

Things are way more modular than they used to be.

I can probably do it again and just try to get attention for it.

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specialist 632 days ago
From the hip, maybe something like "UPDATE DRYRUN ...". It'd report how many rows would be updated.

Or... "DRYRUN UPDATE ...", which is more like "EXPLAIN UPDATE..."

Thoughts?

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progmetaldev 630 days ago
Sounds like a solid idea, but I feel like just replacing your UPDATE with a SELECT COUNT(whatever_column_is_indexed_from_your_where) would be a good practice. If your DBMS supports an external language, that might be the best idea, so you can write your own logic, while keeping mostly everything in the database itself.

I only mean this from a more ANSI SQL side of things, where you might want to build your skills up to use as much of the standard as possible, until it's no longer possible and make sense to dip into platform specifics. I used to build code around being cross-platform, but at the same time realized that it's more useful to learn the ANSI standard, and then break free with LOTS of useful comments where it makes sense to do things more efficiently and with safety that you don't get normally.

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