Jan 14, 2016
Sean Kelly: Required
— A New Mindset
TV vs Radio
OLTPOnLine Transaction Processing— Technology of Live Systems— Stands for Regimes That are:
— Tightly Controlled— Hierarchal— Schedules— Milestones— Deadlines— Detailed Planning
OLAPOnLine Analytical Processing— Iterative Approach— Design is Part of the Process— Your Done When the User Stops Calling
OLTP CULTURE
Core Business Systems Have Become:— Larger— More Powerful— More Complex— More IntegratedRequiring at the Detail Level:— Close Co-ordination— Conformity— Minimization of Creativity
OLTP CULTURE (cont)The Technologies are so Complex:— Difficult to Grasp at Detail Level— Leads to a Culture of:
— Planning— Milestones— Deadlines
— Providing a Common Vocabulary forImplementers and Users
— Wisdom of Secretary Rumsfeld
OLTP CULTURE (cont)
Culture of Procedures has Stood the Test of Time
— Forty Year Geometric Expansion of— Computerized Processes— Data Stored
— Decomposition of Project Provides Managers with a Feeling of
Control
OLTP CULTURE (cont)
SOME DOWNSIDES— Techies Regard Procedures as Drudgery
— Breeds a Culture of Control— Breeds Passive Control
— Experimentation Deemed Inappropriate— Conflicts with Requirement for Timely
Decisions
OLTP CULTURE (cont)
OLTP PROCESS SUCCESSFUL BECAUSE:
— Implementers are Presented With a Design!!
— Already Worked Out— Tested and Refined by Use— Requiring Little Additional Creativity
OLAP CULTURE— Characterized by What It Is Not…— i.e., Not Buttoned Down— Bite Off Small Parts – Partial Projects— Involved Users Test Results as They Occur
— Smaller the Bites, the More Rapid the Adjustments
— Each Partial Project Informs the Next Partial Project–and Overall Strategy
OLAP CULTURE (cont)
OLAP Projects are Characterized by the Way They End
— Battle of Britain— “We Got Up One Day and the Germans Didn’t Come”
— OLAP Projects are Done When the Phone Stops Ringing
OLAP CULTURE (cont)OLAP Approach is Not a Non-Methodology— Users must Review Designs for Completeness
— Typical Business Questions Must Be Answered
— One Type of Query Not Favored over Another
— Methodology Structured to Permit Evolution of Design
OLAP TECHNOLOGY
— Data Warehousing is an Iterative Process;
— The Users Must Be Involved
— OLTP Systems Keep Records— OLAP Systems Provide Information
OLAP TECHNOLOGY
THE FIELD OF DREAMS SCENARIO
— OLAP Systems provide Info for the Non-Routine Parts of User’s Work
— If an OLAP System is Not Intuitive, Users Won’t Use It
— Just Because You Build It Doesn’t Mean That They Will Come
OLTP vs OLAP“Give Us Your Requirements…”
— OLTP: Performs Tasks that are — Structured— Routine
— OLAP: Performs Tasks that are— Wide in Varity— Non-specific— Not Contemplated at Design Time
OLTP vs OLAPOLAP REQUIREMENTS DEVELOPMENT
— Often a Waste of Time— If Enough is Known to Develop Detailed Requirements…
— Its Probably not an OLAP Project
OLTP vs OLAPDETAILED PLANNING OF OLAP
PROJECTS
— Tends to be Self-Defeating Because…— “Planning” by Staff and Users Generates New knowledge, Which…
— Makes Plan Obsolete, Then…— Plan Can’t be Revised without Several
Meetings
OLTP vs OLAPWORKING TO THE RULE
— Technically Sophisticated Users Reluctant to Play, because…
— They Fear that IT will Work to the Requirement, then…
— Declare Victory, and…— Go On to Next Project, Leaving…— User Requirements Met, but…— User Needs Unmet
OLAP:DESIGN & ITERATION
— Physical Design is Crucial— Effective and Robust Design can’t
be Planned…— It Must be Iterated
SEAN KELLY ONCE MORE:The physical database design for the specific industry is THE most Important DW Component. If you don’t have a good PHYSICAL DESIGN, NOTHING else can make up for it:
Not the RDBMS engine Not the front-end tool Not the data extract tool Not technical ingenuity Not the data loading utilities Not more processors Not the business vision
Not even consultants !
OLAP:DESIGN & ITERATION
— Concept Well Known in Data Warehouse Community
— Why are so Many Projects Struggling?— Creeping OLTPization of OLAP Projects
OLAP:THE HISTORY
— Early Data Warehouse Developers Were Left Alone
— OLTP Managers Assumed it would Fail
— Irrational Desire for Useful Information
OLAP:THE SUCCESS
— Some Data Warehouse Projects Succeeded
— OLTP Managers Feared DW Success without Their Assistance – and Worse…
— Not Under Their Control— Doug Hackney: Caché Loosened Purse Strings
OLAP:EXECUTIVE SPONSORSHIP
— OLTP Managers Asserted Control by Imposing Procedures
— Sean Kelly: Executive Sponsorship Means Someone Far Enough Up the Hierarchy to Intimidate IT
— Make IT Knock It Off when it Interferes with the Iterative Process
OLAP:END OF RESISTANCE
— Resistance to Kimball Ended about 6 Years Ago
— Accepting Kimball Did Not Lead to Accepting OLAP
— Creeping OLTPization— Hofer: Competent Bureaucrats Take
Over; Control the New Paradigm
OLAP:THE DECLINE
— Decline in the Importance of Intuitiveness
— Early Technical Selling Point: Intuitiveness
— De-emphasis on Physical Model— Decline of “Push the Decision Down” to Point of Impact
OLAP:QUERY TOOL ATTITUDE
— Vendor Accepts Kimball— Rejects ER Diagram— Suck Up to IT Departments— Commoditization of Product— Emphasis Shifts to Sale of
Services
OLAP:WHATS TO BE DONE
— OLTP Mindset will not Go Away— OLAP Practitioners Must Lead— OLTP Managers Be Brought to See that OLTP Culture is Inappropriate
— Build a Little; Give Users a Little
OLAP:BE INFORMED
— Know What You Know— Don’t be Wimpy
— Keep Users Informed— Keep OLAP Projects in Perspective — Don’t Hype
— Teach Executives the Difference between OLAP and OLTP
— Wisdom of Arthur Fonzerelli
OLAP:THE NEXT GENERATION
— Iterative Process Must Gain Acceptance— OLTP Managers Must become Comfortable
with Iteration— OLAP Leaders will take the Majority of the Grief Because…
— It is They Who Put the Ball in Play
THE END
Ron AllanGeorgetown UniversityPhone: 202-687-8967E-mail: [email protected]://www.georgetown.edu/users/allanr/