This was where I was going as well, but I was going to suggest hashing the larger array instead of the smaller one. I guess I assumed it would be faster to do fewer loop iterations checking for the existence of a key in a larger hash than the other way around. Is this something that would have to be tested on a data set to determine for sure, or is it a for sure thing to do it faster the way you show?

I ask because I've done this exact thing before and I'm curious for an explanation on the efficiency difference.

I love it when things get difficult; after all, difficult pays the mortgage. - Dr. Keith Whites
I hate it when things get difficult, so I'll just sell my house and rent cheap instead. - perldigious

In reply to Re^2: Fastest way to merge (and de-dup) two large arrays? by perldigious
in thread Fastest way to merge (and de-dup) two large arrays? by technojosh

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