view release on metacpan or  search on metacpan

doc/recs-collate.pod  view on Meta::CPAN

             mr_agg(<<[1, {{ct}}]>>, <<[$a->[0] + $b->[0], $a->[1] + $b->[1]]>>, <<$a->[1] / $a->[0]>>)
 
    rec()
    record()
       A valuation that just returns the entire record.
 
    snip(snip)
       Takes a snippet and returns both the snippet and the snippet as a
       valuation. Used to distinguished snippets from scalars in cases where it
       matters, e.g. min('{{x}}') interprets it is a keyspec when it was meant to
       be a snippet (and then a valuation), min(snip('{{x}}')) does what is
       intended. This is used internally by <<...>> and in fact <<...>> just
       translates to snip('...').
 
    subset_agg(<snippet>, <aggregator>)
    subset_aggregator(<snippet>, <aggregator>)
       Takes a snippate to act as a record predicate and an aggregator and
       produces an aggregator that acts as the provided aggregator as run on the
       filtered view.
 
       Example(s):
           An aggregator that counts the number of records with a time not above 6 seconds:
              subset_agg(<<{{time_ms}} <= 6000>>, ct())
 
    type_agg(obj)
    type_scalar(obj)
    type_val(obj)
       Force the object into a specific type. Can be used to force certain
       upconversions (or avoid them).
 
    valuation(sub { ... })
    val(sub { ... })
       Takes a subref, creates a valuation that represents it. The subref will
       get the record as its first and only argument.
 
       Example(s):
          To get the square of the "x" field:
             val(sub{ $[0]->{x} ** 2 })
 
    xform(<aggregator>, <snippet>)
       Takes an aggregator and a snippet and produces an aggregator the
       represents invoking the snippet on the aggregator's result.
 
       Example(s):
          To take the difference between the first and second time fields of the record collection:
             xform(recs(), <<{{1/time}} - {{0/time}}>>)
 
 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
 
 Help from: --help-more:
 Usage: recs-collate <args> [<files>]
    Take records, grouped togther by --keys, and compute statistics (like
    average, count, sum, concat, etc) within those groups.
 
    For starting with collate, try doing single --key collates with some number
    of aggregators (list available in --list-agrregators)
 
 Arguments:
    --dlaggregator|-A ...                         Specify a domain language
                                                  aggregate. See "Domain Language
                                                  Integration" below.
    --aggregator|-a <aggregators>                 Colon separated list of
                                                  aggregate field specifiers. See
                                                  "Aggregates" section below.
    --mr-agg <name> <map> <reduce> <squish>       Specify a map reduce
                                                  aggregator via 3 snippets,
                                                  similar to mr_agg() from the
                                                  domain language.
    --ii-agg <name> <initial> <combine> <squish>  Specify an inject into
                                                  aggregator via 3 snippets,
                                                  similar to ii_agg() from the
                                                  domain language.
    --incremental                                 Output a record every time an
                                                  input record is added to a
                                                  clump (instead of every time a
                                                  clump is flushed).
    --[no]-bucket                                 With --bucket outputs one
                                                  record per clump, with --no-
                                                  bucket outputs one record for
                                                  each record that went into
                                                  the clump.
    --key|-k <keys>                               Comma separated list of key
                                                  fields. May be a key spec or
                                                  key group
    --dlkey|-K ...                                Specify a domain language key.
                                                  See "Domain Language
                                                  Integration" section in --help-
                                                  more.
    --size|--sz|-n <number>                       Number of running clumps to
                                                  keep.
    --adjacent|-1                                 Only group together adjacent
                                                  records. Avoids spooling
                                                  records into memeory
    --cube                                        See "Cubing" section in --help-
                                                  more.
    --clumper ...                                 Use this clumper to group
                                                  records. May be specified
                                                  multiple times. See --help-
                                                  clumping.
    --dlclumper ...                               Use this domain language
                                                  clumper to group records. May
                                                  be specified multiple times.
                                                  See --help-clumping.
    --list-aggregators|--list                     Bail and output a list of
                                                  aggregators