The best solution is dependant of a couple of parameters:
- How often do you run that program (1/day, 1/minute ?)
- How static is the data (do you get new entries every time you run your program?)
- Are you looking for 1 key at a time (in a online app) or do you anyway scan through all the keys in 1 run?

update
Now as we know you have to read all keys anyway just use a hash with your keys and "feed" an array with your data: 
push (@{$myhash{$id}}, "$data");

[download]

pelagic
-------------------------------------
I can resist anything but temptation.

In reply to Re: sort large file by pelagic
in thread sort large file by Murcia

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