I believe I have a solution for your problem that should work with any size files and will finish in less time than it will take to load your data into a RDBMS.

I need confirmation that all your keys (dna sequences) 1) are 9 characters long? 2) consist of combinations of the 5 characters: ACGTN?

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority". I knew I was on the right track :)
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^3: storing hash in temporary files to save memory usage by BrowserUk
in thread storing hash in temporary files to save memory usage by Anonymous Monk

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