It sounds like you think you want a pseudohash. However, from the perlref manpage ...
"WARNING: This section describes an experimental feature. Details may change without notice in future versions."
They are deprecated, I believe, in perl 5.8 and will be removed in 5.10. IOW, you really don't want to use 'em. The fields pragma is the new implementation which should be safe to use. Whether fields will help conserve memory or not I don't know.

However, you probably don't want to do that either. I think you should look at tie()ing the hash to a dbm file. I prefer using GDBM_File in most situations, but you should look at the handy comparison chart in the AnyDBM_File docs before choosing a dbm implementation.

In combination with MLDBM you should be able to work with your data, with a remarkably low memory requirement.

In reply to Re: Array of Hash interface to an Array of Array? by DrHyde
in thread Array of Hash interface to an Array of Array? by Anonymous Monk

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