You are possibly messing with your $fname when you do ($fname,$lname,$age,$dep)= unpack ($pack_rules,$DATABASE{$fname}); and writing back to a different key. Why do you store they key with the data stored under they key ? Do you original derive the key in this way from the data ?

When you say "The problem is that when I look for a key existence in a hash-It gives me 2 keys" you are not making much Perl sense. To check for the existence of a key one usually¹ does exists($hash{$key}) This can only return true/false, it returns no keys, not one and certainly not two :)

what do you see if you put in a print join ", " keys %DATABASE; ? Bet you don't see duplicate keys there so what are you doing to make you think you have duplicate keys ? An example of the code that you use to "look for key existence" would help a lot.

Cheers,
R.

1. I say usually because although I know no other way to check key existence I am not certain there is no other cunning trick known to the brethren

$var=join "," ,keys %DATABASE;
print "$var\n";
that gave me:
Alexander,Dima,Ofir,Udi,Moti,Dima

I've found the problem.
thanks for the help.
Since I read the variables from Entry widgets
It assigns different key in that its' like the previous +
empty space.

a hash which is a dbm file(simple database).

then after modifying something (except $fname of course)

Any suggestions?

I use dbmopen to create/open this dbm database file.
The version of perl is 5.8.6 Activeperl.
The key name and the first variable to pack- have the same
name.
Moreover, the problem doesn't grow further,i.e. When there
already are 2 keys with the same name the last one can be
modified with the mentioned above way.

I use dbmopen to create/open this dbm database file.
The version of perl is 5.8.6 Activeperl.

You're probably using DB_File. Run

perl -MAnyDBM_File -le"print for @AnyDBM_File::ISA"
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to verify.

DB_File (or specifically DB_HASH, which is what you're using) doesn't allow multi-valued keys, so chances are you've misdiagnosed the situation. Insert the following snippet and examine your database

use Data::Dumper;
$Data::Dumper::Indent=1;
$Data::Dumper::Useqq=1;
die Dumper( \%DATABASE );
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you'll be suprised what you find.

Unless you have a good reason to use dbmopen, you should switch to the tie interface.

MJD says "you can't just make shit up and expect the computer to know what you mean, retardo!"

I run a Win32 PPM repository for perl 5.6.x and 5.8.x -- I take requests (README).

** The third rule of perl club is a statement of fact: pod is sexy.

What environment? Are you using strict? are you using global, lexical and local varables? to ONE hash ONE key has ONE name. A key can not exist twice (with the same name) in one hash

$var=join "," ,keys %DATABASE;
print "$var\n";
I see duplicates.

You might be seeing things that *look* the same, but I'm pretty sure they aren't :-)

Try this:

use Data::Dumper;
print Dumper([keys %DATABASE]);
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Does it have duplicate values inside? If so, tell us what those values are.

The problem is that when I look for a key existence in a hash-It gives me 2 keys with the same name but with different values...