hi,
Coming from xbase background and having just started on sql, I tried sql
queries that does xbase 'skip'. I wanted to implement record browsing with
'Next' and 'Previous' features. Currently, I'm testing this with a table of
about 20,000 rows using psql.
I'm able to perform 'forward skip' query with :
=> select * from mytable where id > '12345' order by id limit 1;
- which returned what I wanted, 1 record with id value '12346'. Indexing on
id further optimised the query.
However, I'm unable to optimise query when doing a 'backward skip'. I've
tried :
=> select * from mytable where id < '12345' order by id desc limit 1;
- which returned the correct result '12344', but without optimization.
I was hoping a descending order index key would optimise it, but I think
postgresql don't support it (yet ?).
Next, I tried using offset -1...which is not possible either :)
=> select * from mytable where id > '12345' order by id limit 1 offset -1;
ERROR: parser: parse error at or near "-"
Has anyone tried 'backward skip' with optimization ?
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
