simulating ISAM access with SQL ?

From: Christian Metzler <cme_at_magnet.at>
Date: 1995/08/26
Message-ID: <391049182.25791586_at_magnet.at>#1/1

Hello, is there anybody out there who knows a better solution to the following problem, than I have found:

I want to port an C-tree Application that uses ISAM access, these means: fetch previous record

                       fetch next record
                       fetch last record
                       fetch first record  for a given key

to an SQL database(ORACLE) without changing the logic of the database access functions.

Since in SQL there is no possibility to position a Cursor or to skip up and down in a table the only solution I have found is to use queries like these: Example for simulating fetch previous record: Select col1,col2... from table1 where key1 = (select max(key1) from table1 where key1 < :old_key1)
But this only works if key1 is a unique column.

Any hints for other solutions or crossplatform products are wellcome.

Christian Metzler
Vienna/Austria/Europe
cme_at_magnet.at Received on Sat Aug 26 1995 - 00:00:00 CEST