multiple two way relationships

[SM76]

Hi All, I seriously couldn't come up with a better way of describing the type of relationship I am looking for. The scenario is as follows:

2 tables:

table 1 - students (sname, enrolled course)

table 2 - courses (cname, cstartdate, enrolled students)

What does my relationship model have to look like to be able to:

A) have a student layout, one record being a single student. A portal to all courses that student has enrolled in.

: have a courses layout, one record being a single course. A portal to all students that are enrolled in that course.

Any help greatly appreciated,

Mat

[comment]

You need three tables: Students, Courses and Enrollments. See a very similar example here:

http://www.fmforums.com/forum/showpost.php?post/246136/

[Søren Dyhr]

This is a classical type of relationship:

http://fmpexamples.blogspot.com/2007/06/filemaker-many-to-many.html

BTW ...your skills level??

--sd

[SM76]

Thanks a lot guys, worked out nicely. Your help is much appreciated, as always.

Soren, are you asking what my skill level is or are you questioning my self indicated skill level on my profile? I suppose I had to take a stab at classifying myself for lack of precise guidelines. My thinking was that I'm able to understand the solution you guys present to me, which makes me a bit more than a beginner and yet I very obviously can't come up with it myself, hence only intermediate .. if that assessment misses the mark by a long shot, let me know, I have no problem with downgrading myself to rookie :

cheers

[mr_vodka]

Well many times skill level is asked because some solutions use more advanced techniques than others. It helps those that reply gauge how they should approach the posting.

[Søren Dyhr]

if that assessment misses the mark by a long shot, let me know

If "many to many" relations isn't at the very beginning of every database curriculum, what is then? You might even be drilled sufficiently enough to make some sense of Hegels dialectics right away when exposed to it rudimentary ... but lacking knowledge of which is a prerequisite to the other isn't exactly skills or virtue in the strictest sense, merely training in assumptions.

--sd

[SM76]

well, thanks for your reply, I'm sure it IS at the beginning of every database curriculum .. I simply haven't taken that class.

What I would be curious to know now though are what the underlining statements are that you are making Soren. I hear a few and just want to make sure I'm not putting words in your mouth. Are you saying that everybody who hasn't been trained in databases shouldn't come on here and ask questions? Is it a waste of your time? I just want to make sure I conform by the forum's rules. My impression was that people come here to get help, simply for the obvious fact that people like yourself, who are very skilled, have knowledge to share with people like me. Should I be mistaken, let me know.

[Søren Dyhr]

It has nothing to do with how welcome you should feel to ask questions or not, it's just that I find your skills level elf proclaimed is slightly misjudged, not that you necessarily should humble yourself here in any way - but what is the argument for doing the exact opposite? It is as if we are at war with each other? - a stint of Leviathan perhaps?

All warfare is based on deception. Hence, when able to attack, we must seem unable; when using our forces, we must seem inactive; when we are near, we must make the enemy believe we are far away; when far away, we must make him believe we are near. Hold out baits to entice the enemy. Feign disorder, and crush him

...aren't you seeking allies, by asking questions here? Is the war - marketing warfare?

--sd

[LaRetta]

If "many to many" relations isn't at the very beginning of every database curriculum, what is then?

I do not see a self-rating of Intermediate off base just because someone may not grasp (in one particular situation) that they may require a many-to-many relationship. In fact, some of the really good developers have no professional database training at all (but they have good common sense and an ability to learn). If we are going to begin nit-picking the level and why someone rates themselves as they do, then what will be next ... requiring a resume'?

Edited January 27, 2010 by Guest

[Søren Dyhr]

In fact, some of the really good developers have no professional database training at all (but they have good common sense and an ability to learn)

I would even guess it's the lions share of the community of filemaker developers, but yes I can see that nitpicking about this is wrong ... couldn't we get that thing removed - it's most likely to tell excel-jockey skills instead?

--sd

[RodSierra]

I think this thread is going to take a turn, but one that needs to be discussed a bit. I'm all for removing this from profile data. I see every day people doing nasty things with spreadsheets that could be done so much easily if they simply chose to use a database program, so those out there trying to learn and use FM are the ones taking a chance and deserve the support of those that have the experience, without fear of ridicule. I'm from the group that never had a class in database design, but then again, when I was in school, the computers were the size of a small house. Anyway give them a break they are paving the way to less spreadsheet abuse around the world, no matter what skill level the claim.

[efen]

couldn't we get that thing removed

(If this refers to the self-assessed skill level in the side panel then) I agree with Soren. These skill levels are almost always of little use as a guide to the proficiency of the poster.

There are many instances of posts from "Intermediate" (and even "Advance[d]") users that ask the most basic of questions.

I would guess that the composition of this forum is predominantly people who "dabble" or work with FileMaker, either in a professional capacity or for other purposes, rather than being professional developers.

If a question is asked and the OP cannot understand the answer (because it employs complicated techniques with which they are not familiar) from a forum member then the OP can always post again asking for clarification.

It is interesting that (in many cases) the most competent and knowledgeable people on this forum do not state their skill level. (I hasten to add that I definitely do not class myself in that category - for those who have noticed that my skill level is not shown.)

[Søren Dyhr]

I'm from the group that never had a class in database design

So am I, but lets look at the purpose of the classification, it's exactly as John (Vodka) says it - guidance to the repliers.

When putting your self in the middle of an gaussian curve, should it tell something of how versed you are with the specific tool, and not how litterate or illitterate you find youself with computing as such.

How well would your driving skills translate to a 18 wheeler truck? Something will obviously rub off, but conveyance on a slippery road could be something else?

If you have been replying to questions here would you have noticed that newcomers expect that everyone have hitten exactly the same snags, and skimps upon the context and purpose description. What isn't realized is that each developer approaches the stuff as individually as a fingerprint, so your snags isn't nessersarily the other follows! It takes a lot of practice to learn a trade, and without formal education in the topic, is it highly circumstantial how clever your first take in reality is.

I agree with Malcolm Galdwell when he says that it takes 10000 hours to master a field, an intermediate must then when looking at a gaussian curve be somewhat between 3500 and 6500 hours of practice, in which some sort of relational theory must have sunk in ... perhaps not that all business models falls into 7 relational standard forms allegedly or not ...claimed by the authors of this book:

http://www.amazon.com/Modeling-Theory-Practice-Graeme-Simsion/dp/0977140016

...which I havn't had the oppertunity to read yet! But in my humble opinion, is the odds you havn't thought about many to many relations after say 3500 hours ...very very long, unless the game is a different, say the bluffers???

--sd

[comment]

it takes 10000 hours to master a field, an intermediate must then when looking at a gaussian curve be somewhat between 3500 and 6500 hours of practice

Not necessarily:

http://en.wikipedia.org/wiki/Pareto_principle

[Søren Dyhr]

:girlgiggle:

Well could very easily be what going on with the case with learning curves ... it takes 20% of 10000 hours to master 80% of the curriculum, so until you reach 2000 hours of practice are you ardently excused to be skipping, what otherwise is considered fundamental knowledge?

--sd

[comment]

it takes 20% of 10000 hours to master 80% of the curriculum, so until you reach 2000 hours of practice ...

But it only takes 400 hours to master 64% (80% of 80%). Is 64% "intermediate"? Some people describe themselves as intermediate guitar players because they know four chords - one more than the basic three.

[LaRetta]

Actually, I LIKE having the self-assessment of skills when someone posts. It may not be accurate (according to our individual interpretation) but it gives us another clue on how to proceed. If someone rates themselves Beginner then you can bet we would approach it differently than someone rating themselves Expert.

When all we have are words on a post, every bit of input helps but we should take it in proportion. Proportion is pretty much everything in life ... :wink2:

[Søren Dyhr]

What about a calc'field estimating the skills level, aggregating a list of multiple choises. As well as an urging message next to it, stessing the importance of being earnest in the choises made, of course nowhere near the certification - but to locate weak spots in the knowledge.

--sd

[mr_vodka]

Perhaps 2 more categories that sit in between Beginner --> Intermediate and

Intermediate --> Advanced would make sense.

Also may be we can come up with some descriptions of each type so that users can review them during the self evaluation.

[LaRetta]

That is a great concept, John! :smile2:

[Lee Smith]

I agree.

Link