1. There is no meaningful correlation in the ordering of the records.

    The problem with the picking random (byte) positions, is that with varible length records, longer records have a greater chance of being picked than shorter ones.

    But maybe that is negated to some extent because you would be using the next record--which might be longer or shorter--rather than the one picked?

  2. The file is static. It is only processed once.
  3. It is often huge. Time is of the essence.
  4. Reading the whole file to pick a sample negates the purpose of picking a sample.
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In reply to Re^4: Random sampling a variable length file. by BrowserUk
in thread Random sampling a variable record-length file. by BrowserUk

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