reverse read in KORN shell

WindozBytes · 10-01-2002, 09:57 AM

Is there a way to read a data file ( within a korn shell ) from bottom-to-top rather than from top-to-bottom?

I'm working with some database table that have referential integrity; the tables have to be loaded in a certain order, but unloaded in the reverse order. What I'd like to be able to do is set up one data file with the table names that could be read normally for loading and in reverse order for unloading. Having one file rather than two simplifies maintenance and reduces the chance for mis-matched files.

TIA

stickman · 10-01-2002, 10:58 AM

What format are the data files in? If they are in text format, I'm sure that you could come up with a Perl script with a reverse in it to reorder to data files.

leed_25 · 10-01-2002, 11:47 AM

I don't know if this is appropriate in the KornShell --which I haven't used in many years-- but the general way to do something like this is to read the entire file into a memory array and then to walk through the array forwards or backwards as circumstances dictate.

WindozBytes · 10-11-2002, 07:46 AM

leed_25:
thanks for the suggestion. KORN is extremely limited as far as array processing, but since this task is fairly simple, that turned out to be the easiest way to skin the proverbial cat