Re: SQL scrolling back to a record

[Pete Helgren <pete@xxxxxxxxxx>]

I hear you SETGT with a READEP would be the way to go...but this is a 
Java program using SQL so things get a bit more interesting:

For the others who have weighed in.  The reason for the logic is that I 
have a program the calculates the number of minutes a person has worked 
based on a time clock punch.  A good example of a condition I am try to 
capture is a worker who clocks in at 22:00 on 05-16-2012 and then clocks 
out 0600 on 05-17-2012.  When a report is run for 05-17-2012  this 
employee would have a punch OUT record with no prior punch IN record 
which could be an error or could be a valid punch.  The only way I can 
tell is to check to see what the immediately prior punch for that 
employee would be.  There could have been hundreds of other punch 
records for other employees between the last punch and the prior punch.

So I thought a scrollable cursor would be the way to go.  Grab all the 
records for that employee (could be thousands), locate the specific 
punch I have a question about (the one at 0600 on 05-17-2012), then walk 
back one record and see what the punch is (should be an IN).  The 
problem is (as I discovered last night) that you can't position a 
scrollable cursor by a key value.  You can position by a fixed record 
number or a relative number of records but you can't locate a record in 
the record set by a column value (as far as I can tell).

One way to reduce the number of records would be to just bracket the 
date selection to only include one day prior (otherwise that would be a 
LOOONG shift) so that could reduce the records on a specific employee so 
that walking through the record set to find the record I was interested 
in and then walking back one.

I *think* I can just select the last record for the prior day and see if 
that is the "IN" punch I am looking for but I need to walk through some 
other transactions to see if this will produce a "false positive"

Still sorting through the options but appreciate the feedback so far

Pete Helgren
Value Added Software, Inc
www.petesworkshop.com
GIAC Secure Software Programmer-Java


On 5/18/2012 7:14 AM, sjl wrote:
> Sigh...
> RLA makes this so much easier!;-)
> - sjl