I think that I posted a relevant reply.

In general you want to read the input file(s) once. That is because this is an "expensive" operation in terms of I/O performance.

If you wind up with a scenario where for each line of an input file B, you have to re-read each line of input file A, that is very inefficient. And it will take a lot of MIPs (N*N).

In reply to Re^3: Out of Memory Error : V-Lookup on Large Sized TEXT File by Marshall
in thread Out of Memory Error : V-Lookup on Large Sized TEXT File by TheFarsicle

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