SQL - Select Rows in a Certain Order I'm new here - if I missed anything in the question please let me know.

I'm trying to build a people directory like LinkedIn has:

http://www.linkedin.com/directory/people-a

I don't want to fetch all the rows with name field starting with A and build the link list like LinkedIn. Is there any way in MySQL so I can only fetch rows in this sequence:

1st, 100th,101st,200th,201st,300th,301st,400th,401st, Last

That means I am trying to get two consecutive rows after a certain gap including the first and last item. The ids are not in nice uniformly increasing order.

Say my initial query SELECT * FROM businesses where name like 'a%' order by name returns ids like this:

1,3,5,6,8, 9,12,33,45,66,77,88,100,103,120,133,155,166,177,178,198


Above is if I want to get all the rows. But instead I'm trying to get only the items after a certain distance. For example if I want to pick after every 5 items:

1,(skip 4),9,12,(skip 4), 88,100,(skip 4),166,177,(skip 1),198


So skip 4 items and take next two. Is this possible without fetching all the rows? 

I'm not sure if the above is the best way to achieve what I'm looking for. If you have better solution please let me know.



SELECT * FROM businesses where name like 'a%' order by name this query returns about 50K rows. But I don't need all of them. I'm trying to build people directory that is nested several levels. So, on the first page I'll show links like this:

Page1: http://example.com/people/a
Links: 
   Adam - Alan =&gt; http://example.com/people/a/1   //here I skipped say 1000 people after Adam and before Alan
   Albert - Amy =&gt; http://example.com/people/a/2   // Here I skipped another 1000 people
   ...

Page2: http://example.com/people/a/1
    Here I show all those 1000 people profile links that I skipped in page1.


This is only two level. If you visit the above linkedin link, you'll see 3 or 4 levels of nesting.
This is pretty clumsy but will perhaps give you some thoughts. The idea is to number the rows and pick from there using modulo:

select x from (
    select @n := @n + 1 as n, x 
    from t, ( select @n := 0 ) as dummy
) as u 
where mod(n,6) between 0 and 1 or @n = n


Edit: As observed by @hassansin @n will have the value of the last n. Therefore the union of the last n can be replaced with the predicate @n = n