NoSQL operator: rndtable

Pick one or more records at random from a table.

Usage: rndtable [options]

Options:
    --input (-i) 'file'
      Read input from 'file' instead of STDIN.

    --output (-o) 'file'
      Write output to 'file' instead of STDOUT.

    --help (-h)
      Display this help text.

    --no-header (-N)
      Remove header from output.

    --lines (-L) 'N'
      Pick at most 'N' input records. By default only one
      input record is printed.

    --zero (-z)
      By default at least one record is selected. This option
      specifies that selecting no records is ok.

    --key (-K)
      Instead of printing complete records, just print their
      first (leftmost) field, supposedly the record key.
      This will save us a subsequent call to 'column' if all
      we need is to extract the record keys.

Notes:

Not many tests have been done to assess how uniform is the random
selection of input records.