Re: discussion board based on mysql - numbering format advice ?

[Thimble Smith]

At 19:28, 19990920, chas wrote:
>Maybe I'm misunderstanding you here but this looks like a 
>parent-child relationship. I tried one of these before 
>because it's an infinitely scalable solution .... the problem 
>that I ran into was that displaying an entire thread required 
>a recursion with multiple sql queries. This slowed things down. 

Chas, we had a discussion on trees not too long ago on this list
("recursive subqueries" thread).  The end result is pretty much
that SQL isn't too great for doing this stuff, and you have to
hack around it one way or another.  The elegant hack is to add to
the server a special way of handling graphs.  That's on the TODO
list, but not coming up any time soon.

In the mean time, using a CHAR field w/ a separator seems pretty
reasonable.  Your queries shouldn't be too slow, because MySQL can
use indexes on queries like:

    SELECT * FROM msgs WHERE id LIKE '3.21.14.%';

You might want to make your first message have id '1.0' instead of
id '1'.  That way you can SELECT ... WHERE id LIKE '1.%' and get the
correct results (the entire thread).  If you tried WHERE id LIKE '1%'
then obviously you're going to get '14' and so forth.

Tim