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Instant database clones with PostgreSQL 18

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Re: Instant database clones with PostgreSQL 18

#31

Post by notKilgoreTrout »

ffsm8 wrote: post #29
earthnail wrote: post #25

Earlier quoted context omitted.

Not sure why this is downvoted. For a critical tool like DB cloning, I‘d very much appreciate if it was hand written. Simply because it means it’s also hand reviewed at least once (by definition). We wouldn’t have called it reviewed in the old world, but in the AI coding world we’re now in it makes me realise that yes, it is a form of reviewing. I use Claude a lot btw. But I wouldn’t trust it on mission critical stuf…

Eh, DB branching is mostly only necessary for testing - locally, in CI or quick rollbacks on a shared dev instance. Or at least I cannot come up with a usecase for prod. From that perspective, it feels like it'd be a perfect usecase to embrace the LLM guided development jank

Mostly..

App migrations that may fail and need a rollback have the problem that you may not be allowed to wipe any transactions so you may want to be putting data to a parallel world that didn't migrate.

Re: Instant database clones with PostgreSQL 18

#32

Post by dpedu »

teiferer wrote: post #21
elitan wrote: post #17

For those who can't wait for PG18 or need full instance isolation: I built Velo, which does instant branching using ZFS snapshots instead of reflinks. Works with any PG version today. Each branch is a fully isolated PostgreSQL container with its own port. ~2-5 seconds for a 100GB database. https://github.com/elitan/velo Main difference from PG18's approach: you get complete server isolation (useful for testing migrat…

You mean you told Claude a bunch of details and it built it for you? Mind you, I'm not saying it's bad per se. But shouldn't we be open and honest about this? I wonder if this is the new normal. Somebody says "I built Xyz" but then you realize it's vibe coded.

Huh? It says so right in the README.

https://github.com/elitan/velo/blame/12712e26b18d0935bfb6c6e...

And are we really doing this? Do we need to admit how every line of code was produced? Why? Are you expecting to see "built with the influence of Stackoverflow answers" or "google searches" on every single piece of software ever? It's an exercise of pointlessness.

Re: Instant database clones with PostgreSQL 18

#33

Post by gavinray »

oulipo2 wrote: post #22

Assuming I'd like to replicate my production database for either staging, or to test migrations, etc, and that most of my data is either: - business entities (users, projects, etc) - and "event data" (sent by devices, etc) where most of the database size is in the latter category, and that I'm fine with "subsetting" those (eg getting only the last month's "event data") what would be the best strategy to create a kind…

You can use "psql" to dump subsets of data from tables and then later import them.

Something like:

  psql  -c "\copy (SELECT * FROM event_data ORDER BY created_at DESC LIMIT 100) TO 'event-data-sample.csv' WITH CSV HEADER"
https://www.postgresql.org/docs/current/sql-copy.html

It'd be really nice if pg_dump had a "data sample"/"data subset" option but unfortunately nothing like that is built in that I know of.

Re: Instant database clones with PostgreSQL 18

#34

Post by gavinray »

ffsm8 wrote: post #29
earthnail wrote: post #25

Earlier quoted context omitted.

Not sure why this is downvoted. For a critical tool like DB cloning, I‘d very much appreciate if it was hand written. Simply because it means it’s also hand reviewed at least once (by definition). We wouldn’t have called it reviewed in the old world, but in the AI coding world we’re now in it makes me realise that yes, it is a form of reviewing. I use Claude a lot btw. But I wouldn’t trust it on mission critical stuf…

Eh, DB branching is mostly only necessary for testing - locally, in CI or quick rollbacks on a shared dev instance. Or at least I cannot come up with a usecase for prod. From that perspective, it feels like it'd be a perfect usecase to embrace the LLM guided development jank

  > Eh, DB branching is mostly only necessary for testing - locally
For local DB's, when I break them, I stop the Docker image and wipe the volume mounts, then restart + apply the "migrations" folder (minus whatever new broken migration caused the issue).

Re: Instant database clones with PostgreSQL 18

#35

Post by dpedu »

earthnail wrote: post #25
teiferer wrote: post #21

Earlier quoted context omitted.

You mean you told Claude a bunch of details and it built it for you? Mind you, I'm not saying it's bad per se. But shouldn't we be open and honest about this? I wonder if this is the new normal. Somebody says "I built Xyz" but then you realize it's vibe coded.

Not sure why this is downvoted. For a critical tool like DB cloning, I‘d very much appreciate if it was hand written. Simply because it means it’s also hand reviewed at least once (by definition). We wouldn’t have called it reviewed in the old world, but in the AI coding world we’re now in it makes me realise that yes, it is a form of reviewing. I use Claude a lot btw. But I wouldn’t trust it on mission critical stuf…

It's being downvoted because the commenter is asking for something that is already in the readme. Furthermore, it's ironic that the person raising such an issue is performing the same mistake as they are calling out - neglecting to read something they didn't write.

Re: Instant database clones with PostgreSQL 18

#36

Post by [deleted] »

earthnail wrote: post #25
teiferer wrote: post #21

Earlier quoted context omitted.

You mean you told Claude a bunch of details and it built it for you? Mind you, I'm not saying it's bad per se. But shouldn't we be open and honest about this? I wonder if this is the new normal. Somebody says "I built Xyz" but then you realize it's vibe coded.

Not sure why this is downvoted. For a critical tool like DB cloning, I‘d very much appreciate if it was hand written. Simply because it means it’s also hand reviewed at least once (by definition). We wouldn’t have called it reviewed in the old world, but in the AI coding world we’re now in it makes me realise that yes, it is a form of reviewing. I use Claude a lot btw. But I wouldn’t trust it on mission critical stuf…

[deleted]

Re: Instant database clones with PostgreSQL 18

#37

Post by elAhmo »

teiferer wrote: post #21
elitan wrote: post #17

For those who can't wait for PG18 or need full instance isolation: I built Velo, which does instant branching using ZFS snapshots instead of reflinks. Works with any PG version today. Each branch is a fully isolated PostgreSQL container with its own port. ~2-5 seconds for a 100GB database. https://github.com/elitan/velo Main difference from PG18's approach: you get complete server isolation (useful for testing migrat…

You mean you told Claude a bunch of details and it built it for you? Mind you, I'm not saying it's bad per se. But shouldn't we be open and honest about this? I wonder if this is the new normal. Somebody says "I built Xyz" but then you realize it's vibe coded.

It is the new normal, whether you are against it or not.

If someone used AI, it is a good discussion to see whether they should explicitly disclose it, but people have been using assisted tools, from auto-complete, text expanders, IDE refactoring tools, for a while - and you wouldn't make a comment that they didn't build it. The lines are becoming more blurry over time, but it is ridiculous to claim that someone didn't build something if they used AI tools.

Re: Instant database clones with PostgreSQL 18

#38

Post by pritambarhate »

teiferer wrote: post #21
elitan wrote: post #17

For those who can't wait for PG18 or need full instance isolation: I built Velo, which does instant branching using ZFS snapshots instead of reflinks. Works with any PG version today. Each branch is a fully isolated PostgreSQL container with its own port. ~2-5 seconds for a 100GB database. https://github.com/elitan/velo Main difference from PG18's approach: you get complete server isolation (useful for testing migrat…

You mean you told Claude a bunch of details and it built it for you? Mind you, I'm not saying it's bad per se. But shouldn't we be open and honest about this? I wonder if this is the new normal. Somebody says "I built Xyz" but then you realize it's vibe coded.

Let's say there is an architect and he also owns a construction company. This architect, then designs a building and gets it built from of his employees and contractors.

In such cases the person says, I have built this building. People who found companies, say they have built companies. It's commonly accepted in our society.

So even if Claude built for it for GP, as long as GP designed it, paid for tools (Claude) to build it, also tested it to make sure that it works, I personally think, he has right to say he has built it.

If you don't like it, you are not required to use it.

Re: Instant database clones with PostgreSQL 18

#39

Post by greatgib »

pritambarhate wrote: post #38
teiferer wrote: post #21

Earlier quoted context omitted.

You mean you told Claude a bunch of details and it built it for you? Mind you, I'm not saying it's bad per se. But shouldn't we be open and honest about this? I wonder if this is the new normal. Somebody says "I built Xyz" but then you realize it's vibe coded.

Let's say there is an architect and he also owns a construction company. This architect, then designs a building and gets it built from of his employees and contractors. In such cases the person says, I have built this building. People who found companies, say they have built companies. It's commonly accepted in our society. So even if Claude built for it for GP, as long as GP designed it, paid for tools (Claude) to…

The architect knows what it is doing. And the workers are professionals with supervisors to check that the work is done properly.

Re: Instant database clones with PostgreSQL 18

#40

Post by pebble »

pritambarhate wrote: post #38
teiferer wrote: post #21

Earlier quoted context omitted.

You mean you told Claude a bunch of details and it built it for you? Mind you, I'm not saying it's bad per se. But shouldn't we be open and honest about this? I wonder if this is the new normal. Somebody says "I built Xyz" but then you realize it's vibe coded.

Let's say there is an architect and he also owns a construction company. This architect, then designs a building and gets it built from of his employees and contractors. In such cases the person says, I have built this building. People who found companies, say they have built companies. It's commonly accepted in our society. So even if Claude built for it for GP, as long as GP designed it, paid for tools (Claude) to…

No, it's more like the architect has a cousin who is like "I totally got this bro" and builds the building for them.
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