help w/ complicated php-mysql search

[Anon]

I'm creating my own forum system.

Right now, I'm using a database structure somewhat similair to phorum.

My relavant fields for each post are:
id int auto_increment primary
parent int

Now, any post with '0' in it's field is a topic is a new topic and may or may not have children.

I want to add numbers at the bottom of my page like, << 1 2 3 4 5 >>

These will let you navigate through the posts by topic.

Now, the problem is, I only care about getting the topics, not the children of topics. But I can't find a good way of only nabbing the ID's of new topics.

I need to find a good algorithm/php-mysql function that will loop through the total number of posts with '0' as a parent, divide this by the number of posts I show per page, and create a variable I can place in my URL that will let me display the topics poast the given point.

[factory21]

This sounds like a basic pagination problem: breaking up many records into pages.

check out the LIMIT specifier for MySql SELECT queries. It lets you specify which record to start and end at.

An alternative method is to select everything and cache it in the session. Or you can do a hybrid of both (cache several pages and re-load as necessary).

So...your query would look something like:

SELECT * from topics WHERE parentid=0 LIMIT 0,10

for the first page, with 10 records/page and then for the second page:

SELECT * from topics where parentid=0 LIMIT 10,10

the only other query you need is one to tell you the total number of records so that you can display all the page links:

SELECT count(*) from topics where parentid=0

[Anon]

I didn't realize LIMIT had an 'offset' value you could pass in.

That works perfectly, thanks 🙂