(RFD) Which would you prefer next?

[motorollin]

+1 for the knowledge base. I would like to see a kind of intelligent knowledge base which can take user input into account when presenting its answer. Take the old chestnut of "how do I copy files from my PC to my Amiga?". The answer will depend very much on the user's hardware configuration. So the knowledge base document could contain a series of tick-boxes, such as:

- My Amiga has Workbench 1.3
- My Amiga has Workbench 2.04
- My Amiga has Workbench 3.0+

- My Amiga has a floppy drive
- My Amiga has a hard drive
- My Amiga has a CD-ROM drive
- My PC has a floppy drive
- My PC has a CD-Writer

- My Amiga has a network card

etc. The knowledge base then presents an answer which is appropriate for the user's hardware (e.g. burning to CD if the user's PC has a burner and Amiga has a CD-ROM, or using floppies if both machines have floppy drives and the Amiga is able to read from MS-DOS disks etc. Clearly some more desirable answers would take priority over others if more than one is applicable.)

I know that this is probably asking a lot if there is no existing back-end to support this type of knowledge base. I'm just making the suggestion in case there is. And I would be prepared to write some documents. The idea of writing it once and then being able to link to the article whenever somebody else asks the question is very appealing.

[motorollin]

Don't stop there start coding...

Actually I am thinking about it. Shouldn't be too hard to knock up the code. It's just a case of integrating it with a.org.

[motorollin]

You can join a single table multiple times in a query by using an alias name for each invocation of the join. However, building up large queries with a lot of joins and dependencies is not often a good idea, especially where these are generated from code. It's possible to end up generating queries that can never actually complete if you aren't careful.

Could you give me an example of a situation where this might happen? Surely the worst case scenario is that no records are returned?

[motorollin]

almost but you need to join the C table.

Oh yes... it would have taken me a while to spot that when it didn't work

You may have only heard of joins but you are already using them

AND B.solution_id = A.solution_id

is a join (implicit)

Ahh ok. I learned how to do this from a guy where I used to work when I was thrown in a the deep end developing an asset tracking and management app in PHP/MySQL. He referred to them as linked tables not joins, though if I switched my brain on I probably could have spotted the similarity between the words "link" and "join"

I recommend some reading up a bit of sql and database design. will save time later on not making mistakes early on in your schema.

I usually just try it and see what happens then read if I need to. Can I just do that please?

[motorollin]

@Wayne
NP, thanks for moving the OT stuff. I got carried away

Edit - you missed a couple of posts BTW.