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NAME

recs-topn

recs-topn --help-all

Help from: --help-basic:
Usage: recs-topn <args> [<files>]
   Outputs the top n records from input stream or from <files>. You may segment
   the input stream based on a list of keys such that unique values of keys are
   treated as distinct input streams. This enables top n listings per value
   groupings. The key values need not be contiguous in the input record stream.

   --key <keyspec>              Comma separated list of fields. May be specified
                                multiple times. May be a keyspec or keygroup,
                                see '--help-keys' for more
   --topn | -n <number>         Number of records to output. Default is 10.
   --delimiter <string>         String used internally to delimit values when
                                performing a topn on a keyspec that inlcudeds
                                multiple keys. This value defaults to "9t%7Oz%]"
                                which may - under unusual and bizarre corner
                                cases - cause false positive key matches if your
                                values contain this value. You can set this to
                                any string.
   --filename-key|fk <keyspec>  Add a key with the source filename (if no
                                filename is applicable will put NONE)

  Help Options:
      --help-all        Output all help for this script
      --help            This help screen
      --help-keygroups  Help on keygroups, a way of specifying multiple keys
      --help-keys       Help on keygroups and keyspecs
      --help-keyspecs   Help on keyspecs, a way to index deeply and with regexes

Examples:
   Output just the top 5 records
      cat records | recs-topn -n=5
    (this is equivalent to executing "cat records | recs-grep '$line < 5'")

   Output just 10 records for each area
      cat records | recs-sort --key area | recs-topn -n=10 --key area

   Output the top 10 longest running queries per area and priority level
      cat records | recs-sort --key area,priority,runtime=-n  | recs-topn -n=10 --key area,priority

Help from: --help-keygroups:
KEY GROUPS
   SYNTAX: !regex!opt1!opt2... Key groups are a way of specifying multiple
   fields to a recs command with a single argument or function. They are
   generally regexes, and have several options to control what fields they
   match. By default you give a regex, and it will be matched against all first
   level keys of a record to come up with the record list. For instance, in a
   record like this:

   { 'zip': 1, 'zap': 2, 'foo': { 'bar': 3 } }

   Key group: !z! would get the keys 'zip' and 'zap'

   You can have a literal '!' in your regex, just escape it with a \.

   Normally, key groups will only match keys whose values are scalars. This can
   be changed with the 'returnrefs' or rr flag.

   With the above record !f! would match no fields, but !f!rr would match foo
   (which has a value of a hash ref)

   Options on KeyGroups:
      returnrefs, rr  - Return keys that have reference values (default:off)
      full, f         - Regex should match against full keys (recurse fully)
      depth=NUM,d=NUM - Only match keys at NUM depth (regex will match against
                        full keyspec)
      sort, s         - sort keyspecs lexically

Help from: --help-keyspecs:
  KEY SPECS
   A key spec is short way of specifying a field with prefixes or regular
   expressions, it may also be nested into hashes and arrays. Use a '/' to nest
   into a hash and a '#NUM' to index into an array (i.e. #2)

   An example is in order, take a record like this:

     {"biz":["a","b","c"],"foo":{"bar 1":1},"zap":"blah1"}
     {"biz":["a","b","c"],"foo":{"bar 1":2},"zap":"blah2"}
     {"biz":["a","b","c"],"foo":{"bar 1":3},"zap":"blah3"}

   In this case a key spec of 'foo/bar 1' would have the values 1,2, and 3 in
   the respective records.

   Similarly, 'biz/#0' would have the value of 'a' for all 3 records

   You can also prefix key specs with '@' to engage the fuzzy matching logic

   Fuzzy matching works like this in order, first key to match wins
     1. Exact match ( eq )
     2. Prefix match ( m/^/ )
     3. Match anywehre in the key (m//)

   So, in the above example '@b/#2', the 'b' portion would expand to 'biz' and 2
   would be the index into the array, so all records would have the value of 'c'

   Simiarly, @f/b would have values 1, 2, and 3

   You can escape / with a \. For example, if you have a record:
   {"foo/bar":2}

   You can address that key with foo\/bar

SEE ALSO