Paging from DB level or Application level .

Question

Hi All,
Just wonder if anyone if you guys can give me some ideas no implementation of paging. How would normally paging be done? To be more exact, my question is referring that the paging should be done :
1. SQL Level
Here the retrieval of records are queried into block of record. ie: within
range of 1-10, 11-20. There will be likely multiple hit to DB.
2. Application level(jsp)
Here the retrieval of records are queried from one SQL stmt. ie:
select * from table where name = '';
Then if it returns more 10 rows, paging is done at application level.
The first option will reduce the network usage in terms of bandwidth.
Kindly advice asap.
And appreciate if u can give me any good links for reading
Thanks.

Answer 1

It also depends on whether the data retrieved must be consistent. For example, I issue a search for records. The search completes and I receive the first page of results. I navigate to the second page. A user subsequently adds a new record that would have displayed on the first page.
So what should happen if I hit 'back'?
Option 1 is that I use database pagination methods. In this case, I will see the new record when I hit 'back'.
Option 2 is that I cache the results in memory (if the result set is small) or to the filesystem (if the result set is large). In this case, I will see the same page as before.Neither implementation is 'right'. It depends on the behavior that is required. Reports, for example, probably should not use method 1. However, searches probably do not need the snapshot produced by method 2.
If you do want to save the snapshot, be sure to consider serializing it to the filesystem. I normally create one file per page and populate the data there directly. The files are named [session_id]-[page number]. However, you have a considerable amount of freedom in how you approach this.
- Saish