What is wrong with this script?

[David Farr]

The following script writes various symbols (letters) to a field; they represent ranges. My letters are filtered based on this field. However, sometimes the script gets "stuck" on one symbol and writes it to the rest of the records until it reaches the end of the file. The thing is that it doesn't always happen, but it is happening to a client and I need to find the problem. Here is the applicable part of the script (all variables have been defined earlier in the script):

t=table.open("master")
t.index_primary_put("days_od")
t.batch_begin()
t.fetch_first()
while .not. t.fetch_eof()
if between(t.Days_od,sdaysaging1ll-2,sdaysaging1ll) then
bal="B"
elseif between(t.days_od,sdaysaging2ll-2,sdaysaging2ll) then
bal="C"
elseif between(t.days_od,sdaysaging3ll-2,sdaysaging3ll) then
bal="D"
elseif between(t.days_od,sdaysaging4ll-2,sdaysaging4ll) then
bal="E"
else
bal="X"
end if
t.change_begin()
t.newer=bal
t.change_end()
t.fetch_next()
end while
t.batch_end()
t.close()

I have had this problem many times when writing scripts like this in the past but the problem usually magically goes away. What am I doing wrong? It seems to me that after the fetch_next() the system is not reading the if statement anymore, just changing records. Do I need an xbasic_wait_for_idle() in there somewhere? Is there a better approach? Thanks in advance for any comments.

Dave

[Peter.Wayne]

RE: What is wrong with this script?

have you tried removing the batch_begin() and batch_end() statements?
have you verified that each record contains a non-null value for t.days_od?

[JerryBrightbill]

RE: What is wrong with this script?

Dave

While this should probably have no bearing on the problem, I would switch to a select case command rather than if statements. Select case is a little faster in many cases. If the problem is a timing isue, this might help.

To add to what Peter said, I would also use the first case statement to eliminate records that don't have a valid value for any of the fields used. Even though there should be values in the fields, it is good to use code to verify. This eliminates many potential errors. You could use a similar methodology to stop the script if the variables don't populate correctly.

select
case alltrim(cdate(t.Days_od)) = ""
case between(t.Days_od,sdaysaging1ll-2,sdaysaging1ll)
bal="B"
'and so one
end select

Also you don't need the value in the else statement, just set the bal to a default of "X" before whatever you use to set the values.

Bal = "X"
'then the code

Another troubleshooting idea is to send every value to the trace window during the process to see exactly what is being evaluated.

trace.writeln("days_od = "+dtoc(t.days_od))
trace.writeln("aging1ll = "+dtoc(sdaysaging1ll))

and so one. After the script runs, open the trace window and see how the values developed.

Jerry

[David Farr]

RE: What is wrong with this script?

Jerry and Dr. Wayne,

Thanks for your replies, I realize now that I have not accounted for the likely possibility of having null values. Also, select case is what I should have gone with in the first place, as well as setting the default value for the field. I believe you have helped me out of a bind and I greatly appreciate it!

Dave

[David Farr]

RE: What is wrong with this script?

One more thing: Is it a good idea to eliminate the batch commands? Can they cause potential problems? I have about 15,000 records and am looking for speed....do the batch commands help out?

[JohnZaleski]

RE: What is wrong with this script?

Batch commands are not problematic.I'm sure Peter was just giving you something to try.You don't have to ask do they help, you can find out yourself.

Put a "t1 = toseconds(time())" at the beginning
Put a "t2 = toseconds(time())" at the end

Then have this line at the very end of the script
trace.writeln("Trial 2 - Seconds elapsed:" + str(t2-t1))

Then run the script with and then without the batch commands.