Question

I want to return only the last 15 rows in my table, then the 15 before that.

Unfortunately while($rows = mysql_fetch_assoc($result)) where the query is SELECT * FROM table returns the data in all rows.

I thought about doing something like:

In my insert script

SELECT * FROM table then $selection_id = mysql_num_rows($result)-14 before inserting any data, then adding column named selection_id which would contain $selection_id, thus each set of 15 rows would have the same selection_id.

In my select script

SELECT * FROM table then $num_rows = mysql_num_rows($result)/15 then SELECT * FROM table WHERE selection_id='$num_rows' and SELECT * FROM table WHERE selection_id='$num_rows-1'.

I could then perform while(..) on both results as usual.

However, I’m not sure this is the most efficient way (chances are it’s not), so if not, I’d really appreciate some suggestions to cut down the amount of code I’ll have to use :)!!

Answer 1

Use a LIMIT clause in your query, order by your auto-incrementing primary key in descending order. E.g.

SELECT * FROM `table` ORDER BY `selection_id` DESC LIMIT 0,15

…will get the last 15 rows, and:

SELECT * FROM `table` ORDER BY `selection_id` DESC LIMIT 15,15

…will get the 15 rows before that.