[jira] [Commented] (MADLIB-909) Sessionization - Phase 1

["ASF GitHub Bot (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/MADLIB-909?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15421319#comment-15421319 ] 

ASF GitHub Bot commented on MADLIB-909:
---------------------------------------

Github user fmcquillan99 commented on the issue:

    https://github.com/apache/incubator-madlib/pull/63
  
    Looks good, here are my minor suggestions:
    
    new features section:
    
    (1)
    +* New function: Sessionization (MADLIB-909, MADLIB-1001)
    
    (2)
    +* New function: Pivot (MADLIB-908, MADLIB-1004)
    +    Added a function to do basic OLAP type operations on data stored
    +    in one table and output the summarized data to a second table.
    
    (3)
    +* PGXN:  Update PostgreSQL Extension Network for latest release (MADLIB-959)
    
    
    bug fixes section
    
    (4)
    +* User documentation improvements including for hypothesis test docs (MADLIB-1001)
    
    (5)
    +* madpack uninstall support for Apache HAWQ 2.0+



> Sessionization - Phase 1
> ------------------------
>
>                 Key: MADLIB-909
>                 URL: https://issues.apache.org/jira/browse/MADLIB-909
>             Project: Apache MADlib
>          Issue Type: New Feature
>          Components: Module: Utilities
>            Reporter: Frank McQuillan
>            Assignee: Nandish Jayaram
>              Labels: gsoc2016, starter
>             Fix For: v1.9.1
>
>
> Story
> As a data scientist, I want to perform session reconstruction on my data set, so that I can prepare for input into other algorithms like path functions, or predictive analytics algorithms.
> Details
> 1)  The PDL Tools module sessionization module [1] is one example implementation.  Source code is located at [2].  Also see [7].
> 2) How to sessionize.  PDL Tools uses a time based session reconstruction that defines a session as a sequence of events by a particular user where no more than n seconds has elapsed between successive events.   That is, if we don’t see an event from a user for n seconds, start a new session.   The requirement for  MADlib is similar but with the following addition:
> * generalize partition expression
> 3) Proposed interface:
> {code}
> sessionize (
>    source_table,
>    output_table,
>    partition_expr,
>    time_stamp,
>    max_time)
> {code}
> where
> output_table
> add 2 new columns to the source_table:  session_id and new_session:
> * session_id=1,2, ...n where n is the number of sessions in the partition
> partition_expr
> VARCHAR. The 'partition_expr' can be a single column or a list of comma-separated columns/expressions to divide all rows into groups, or partitions. Matching is applied across the rows that fall into t he same partition. This can be NULL or '' to indicate the matching is to be applied to the whole table.
> time_stamp
> Column name with time used for sessionize calculation.  Cannot be a PostgreSQL ORDER BY expression.  This is simply a column name.
> max_time
> Delta time between subsequent events to define a sessions, i.e., session timeout.
> Questions
> 1) Q: Do we need separate 'order_expr' and  'time_stamp' columns?  Aster does it this way.
> A: No, we can't come up with a reason why a user would need this.  If we want to add later, we can add as an optional parameter.
> 2) Q: What to do if negative delta_t between events?
> A: Do not include in session and output a warning message.
> References
> [1]  PDL Tools sessionization module
> http://pivotalsoftware.github.io/PDLTools/group__grp__sessionization.html
> [2] PDL tools source code
> https://github.com/pivotalsoftware/PDLTools
> [3] Blog on bot signatures from Akamai
> https://blogs.akamai.com/2013/06/identifying-and-mitigating-unwanted-bot-traffic.html
> [4] Aster Analytics users guide, see "sessionize" function
> http://www.info.teradata.com/edownload.cfm?itemid=143450001
> http://www.info.teradata.com/templates/eSrchResults.cfm?txtpid=&txtrelno=&prodline=all&frmdt=&txtsrchstring=aster%20analytics&srtord=Desc&todt=&rdSort=Date
> https://www.youtube.com/watch?v=C760M9ttK9Q
> [5] General information on sessionization
> https://en.wikipedia.org/wiki/Session_(web_analytics)
> [6] See path function for partition and order by params
> http://madlib.incubator.apache.org/docs/latest/group__grp__path.html
> [7] SQL sessionization example from blog
> https://blog.pivotal.io/pivotal/products/time-series-analysis-1-introduction-to-window-functions
> [8] Postgres example of SQL based sessionization
> http://randyzwitch.com/sessionizing-log-data-sql/



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)