nice thread. I would treat the file as a database

a unix solution would be

  • cut the kill file in k chunks
  • fast string matching on serial file via grep
    • grep -nF -f chunk serial_file > delete_file # you need k steps!
  • perl gets line numbers n from delete_file, for each n susbstitute in serial the line by "X" x length $_

    if latter you add entries put it at the first X line that fits or else append

    (update) if you need to repeat the process a few times, maybe it's worth to sort the serial file

    In reply to Re: 15 billion row text file and row deletes - Best Practice? by sgt
    in thread 15 billion row text file and row deletes - Best Practice? by awohld

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