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Comment by geezerjay | Hacker News Reader

> I didn't know creating a 3rd table to track Reputation/Likes between a user and a Story is a database concept called 'Joint Table'.

That's a major problem. Table joins are the most basic concept in relational databases. A so called developer who puts together a database but isn't even aware of table joins is someone who didn't even browsed through a basic SQL tutorial and is completely oblivious to concepts such as database normalization.

To put it in perspective, it's like claiming you are a proficient developer but are oblivious to the use of if statements.

If you're really interested in software development and web services I'd suggest you invest a couple of hours learning the basics of relational databases, including a brief intro to normalization. That is mandatory if you want to avoid more accusations of incompetence.

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Uh, "joint table" was the term used, not "table join". Pretty sure "joint table" in this context is referring to something like the intermediary table in a many-many relationship, which I can see being quite intuitive to create without knowing this weird term that I've never heard of before, either.

I have always referred to it as a joining table

Potayto potahto https://stackoverflow.com/questions/3045034/whats-the-correc...

I call BS if they "take points off" for not knowing the exact term "joint table", and if so that's not the kind of company I'd want to work for.

You call BS on OP or the interviewer? Have you interviewed for a "unicorn" and other "cool" companies?

Sadly, looking for excuses to rationalised that the interviewer doesn't like you is still a thing.

I call BS on the interviewer because as this thread and that question I linked on Stack Overflow demonstrates, "joint table" is not "the" term for the concept in question, and in fact there is no accepted one term. So, "marking down" for not knowing that term doesn't seem right.

Edit: On the other hand, asking the question in a way that gets at the concept, not the term, seems very reasonable.

I don't think it's relevant, but yes, I have interviewed at such companies.

> Uh, "joint table" was the term used, not "table join".

I don't believe OP is aware of the existence of table joins, and just reproduced what he thought was mentioned.

Meanwhile, the DB operation he described is clearly a table join (create a new table by creating a relationship between two existing tables).

That is also quite clearly a good reason for a prospective employer to lose interest in OP as a potential recruiter, and why his projects on Github fail to impress anyone. Portfolio projects only work in favor of a job applicant if they are any good, but if they are all a bunch of crap that is poorly put together and showcases incompetence, such as setting up a database system that tries to reinvent the wheel to fill in the gap of not knowing the very basics, then obviously that is disheartening to any potential recruiter.

What the hell else do you think they were doing with their "joint table" if not performing joins on it?

"Joint Table", not "Table Join", they are very different things. You can use joint tables a lot without even knowing that they are called joint tables.

To be fair, I think the OP knows what are joins, but doesnt know what are “Joint Tables”. I literally never heard the term “Joint Tables” myself until now.

> I literally never heard the term “Joint Tables” myself until now.

I don't think this is an SQL concept. The only people I've heard use this word (phrase?) are people who work with Java ORMs.

Ditto. And a Google search shows a full page of "table joins" for "joint table." Still not sure what a joint table is.

It's a table that tracks the people who smoke.

Also never heard of that phrase. I also haven't called them "join tables", but that at least seems a more sensible phrase and is a close homonym to "joint tables".

Yeah, as I said, did a hundred things. I designed database schema without picking up a single book on database. First implementation was 100 DB accesses per Story fetch, and it blew the cap on my BaaS in days of development. LOL. Quickly figured out what's wrong via API documentation, redesigned the schema (I didn't even know what the word schema is, I thought it's just Excel table rows & columns). Shrunk it down to 0 accesses for query actions (query also fetch basic metadata for 50 Stories at the same time). Probably got all these done in 2/3 weeks, a quarter of the time someone goes thru a DB design course?

It's really hard to even recall dozens of these experience and shrink them into stories and putting words to these. In the startup world, it's called 'Get Shit Done'. In the monolithic FAANG & FAANG wannabe world, I dunno what it's called...

See Associative entity [1] for list of common names for "join table"

[1] https://en.m.wikipedia.org/wiki/Associative_entity

Since most of my sibling comments are sharing anecdotes I therefore admit that I have heard the term.

Maybe if everyone replies if they have heard it or not we can reach a conclusion if it is a known term in Hacker News community.

Or we can decide that such anecdotes are of little value to the discussion and stop posting them since it is unrealistic to reach the above mentioned conclusion just by reading them and it can mislead some readers.

Never heard of the term even though I am using them all the time.

Any resources for learning rdb concepts? I'm not particularly skilled in the theory yet I'm sure I've (poorly?) reinvented many common patterns...

https://lagunita.stanford.edu/courses/DB/2014/SelfPaced/abou...

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