Hello Perl Monks. First time post, long time gleaner of information which is and has been very appreciated. Anyway I have an issue that I truly need some assistance with. I am fairly new to hash tables. What I need to do is compare three hash tables each containing between 14 million and 28 million keys with associated values. Sure, I could nest some loops and let it rip and come back in a year or so to see if it worked and hoping that no server crashes occurred.

Optimally, I'd like to find the common keys between each of the three hash tables and gather the values from each of the three hash tables and create a new, forth hash table that contains  key => [value_hash_1, value_hash_2, value_hash_3] And for a key that does not exist in all three hashes, do nothing; the resulting forth hash table will have somewhat less than 14 million k/v pairs.

Do I make sense? And the solution is most likely posted, but I had difficulty finding it.

Thank you very much for your assistance!

In reply to multiple hash compare, find, create by Anonymous Monk

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