Help with next/previous images

[jreid]

Hi all,
First post to this forum. Learning PHP/mySQL

I am writing a db driven image gallery.

My table structure is as follows
TABLE 1:

Name: gallery_category

Field 1: gallery_id (PRI KEY auto-inc NOT NULL)
Field 2: gallery_name (VARCHAR)

Table 2:
Name: gallery_photos
Field 1: photo_id (PRI KEY auto-inc NOT NULL)
Field 2: photo_filename (VARCHAR)
Field 3: photo_caption (VARCHAR)
Field 4: category_id (INT)

OK, so I can successfully query the database and pull out a pic based on variables sent with the link $cid and $pid

My problems are:
I don't have a way of automatically selecting the "first" image in a category (I want them to be displayed in a particular order) since photo with photo_id = 5 may actually be the first record in the database for a particular category.
Should I add a photo_order column?

I want to find a way of putting a 'smart' next and previous link on the page. Smart as in it knows when it gets to the last and or first pic of a category. I know this will involve a count of rows returned from a query based on category, but can't figure the best steps to take after that...

Any help greatly appreciated...

jreid

[python_q]

It's pretty simple to sort:
"SELECT * FROM gallery_photos
WHERE category_id = $cid
ORDER BY photo_filename or whatever field you want to order them by"

And if you just want to get the first photo, then tack on a LIMIT 0,1

As far as making "smart" prev/next buttons, I'm a little too tired to write out the code, but you'll have to get an array of all the photo_id's in the category then search for the values right before and right after the current $pid.

[jreid]

Will give it a try, thanks very much
I have an idea of how to achieve the next/prev thing too.
Thanks again, get some rest.

Jon