> Hmm you seem to be laboring under a concept that to know how to join two tables you need to be an RDBMS "expert"
You're misreading. You kept bringing up the point of "expert" knowledge (e.g. in C and for-loops), or knowledge of RDBMSes, and saying you couldn't know X without also knowing Y.
As the question was about SQL, NOT RDBMSes or "expert"-level knowledge of SQL or RDBMSes, I pointed that out.
> On the contrary, if you can't join two tables with SQL, you don't have any "working knowledge of SQL".
Depends on what "can't" you're talking about. I can look it up and then do it. A lot of people don't remember the syntax. Obviously anyone with working knowledge CAN do a join; the question was whether they could tell you how to do it off the top of their head.
Even things you've used a lot, if you haven't used them recently, you'd likely slip up in an interview.
> Every answer you make exposes the hollowness of your supposed "working knowledge"!
Not really. I can make things work (hence "working knowledge") and look up what I don't know and use it right away.
I've been using in-memory databases and of course the equivalent of a JOIN is a basic function but it's not an SQL JOIN.
You're misreading. You kept bringing up the point of "expert" knowledge (e.g. in C and for-loops), or knowledge of RDBMSes, and saying you couldn't know X without also knowing Y.
As the question was about SQL, NOT RDBMSes or "expert"-level knowledge of SQL or RDBMSes, I pointed that out.
> On the contrary, if you can't join two tables with SQL, you don't have any "working knowledge of SQL".
Depends on what "can't" you're talking about. I can look it up and then do it. A lot of people don't remember the syntax. Obviously anyone with working knowledge CAN do a join; the question was whether they could tell you how to do it off the top of their head.
Even things you've used a lot, if you haven't used them recently, you'd likely slip up in an interview.
> Every answer you make exposes the hollowness of your supposed "working knowledge"!
Not really. I can make things work (hence "working knowledge") and look up what I don't know and use it right away.
I've been using in-memory databases and of course the equivalent of a JOIN is a basic function but it's not an SQL JOIN.