Sybase offset for pagination

Question

Is there any simple way to implement pagination in sybase? In postgres there are limit and offset in mysql there is limit X,Y. What about sybase? There is top clausure to li

Answer 1

Unfortunately Sybase does not provide the ability to set a start and offset limit. The best you can achieve is to use the SET ROWCOUNT to limit the number of records returned. If you have 1,000 records and want to page by 50 entries then something like this will bring back the first page...

set rowcount 50
select * from orders

For the second page...

set rowcount 100
select * from orders

...and then you can choose not to display the first 50 from within your Java code. Obviously as you page forward you end up having to return larger and larger data sets. Your question about what to do with 1,000,000 records doesn't seem practical for a user interface that is paginated. No user searches on Google and then pages forward 1,000 times looking for stuff.

What if I have a Natural Key?

If you do have a relatively large data set and you can use a natural key on your data, this will help limit the records returned. For example if you have a list of contacts and have an interface that allows your users to select A to Z to page the people in the directory based on Surname then you can do something like...

set rowcount 50
select * from people 
where upper(surname) like 'B%'

When there are more than 50 people with a surname starting with 'B' you use the same approach as above to page forward...

set rowcount 100
select * from people 
where upper(surname) like 'B%'

... and remove the first 50 in Java code.

Following on from this example, maybe you can limit searches by date, or some other piece of data meaningful to your users requriements.

Hope this helps!