OpenEuphoria

Re: a few questions

• Posted by Irv Mullins <irvm at ellijay.com> Jul 30, 2001
• 359 views

> In EU data base I see no way to perform a 'read next' or 'read previous'
> type function. I would like to be able to do this and get the data
elements
> out in sorted (by key) order. Is this do'able? The are apparently stored
in
> sorted order since a binary search is done with a db_find.

The keys are stored in sorted order with the base.
To read them all, loop from 1 ... db_table_size()
To select the prev or next record, either keep a counter,
or, if you have done a lookup, and want the previous or next
record from that point:
  x = db_find_key(IHaveThisKey)
 if x > 0 then -- key was found, so
   prevkey = db_record_key(x-1)
   nextkey = db_record_key(x+1)
   nextdata = db_record_data(x+1)...

You may want to put some sanity checks on x before you try to retrieve
record numbers
less than 1 or higher than the size of the table.

Regards,
Irv