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Two Neglected Data Management Technologies
Data Profiling & Database Archiving
DAMA Phoenix Chapter9 September, 2010
Jack E. Olson
www.svaltech.com
SvalTech
“Data Quality: The Accuracy Dimension”, Morgan Kaufmann, 2003“Database Archiving: How to Keep Lots of Data for a Long Time", Morgan Kaufmann, 2008
Copyright SvalTech, Inc., 2010
2
Why Two Topics
Copyright SvalTech, Inc., 2010
SvalTech
• Jack knows a lot about each of them– Wrote a book on data profiling– Wrote a book on database archiving– Built data profiling product: AXIO at Evoke– Built database archiving product: TITAN at NESI
• Both are post-operational data management technologies
• Neither is required for operational purposes
• Both have huge potential for return on investment– Cost savings– Operational performance improvements– Risk reduction
• Both are liked by compliance/governance folks
• Both are under-utilized in IT shops
3
What I’m Going to Talk About
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SvalTech
For each Technology,
• Define Technology• Identify Where It is Used• Show How it Works• Basic Solution Architectures• Show Business Case Basics• Why it is Neglected
4
Data Profiling
SvalTech
Copyright SvalTech, Inc., 2010
5
Books
Copyright SvalTech, Inc., 2010
SvalTech
• Data Quality: The Accuracy Dimension, Jack E. Olson, Morgan Kaufmann, 2003
• Executing Data Quality Projects” Ten Steps to Data Quality and Trusted Information (tm), Danette McGilray, Morgan Kaufmann, 2008
• Three Dimensional Analysis – Data Profiling Techniques, Ed Lindsey, Data Profiling LLC, 2008
• Data Quality Assessment, Maydanchik Arkady, Technics Publications, LLC, 2007
6
Definition
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SvalTech
Data Profiling is the application of data analysis techniquesto existing data for the purpose of determining the actual content, structure, and quality of the data.
Data
Profiling
metadata
accurate &
inaccurate
Data
accurate &
inaccurate
accurate
metadata
facts about
inaccurate
data
data quality
issues
7
Where is Data Profiling Used?
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SvalTech
• Enterprise Data Quality Improvement Program– Traditional Six Sigma Like Program– Recursive application of data quality assessment– Based on historical success of companies who have used it
• Support Consolidation of Databases after mergers and acquisitions– Dramatically reduce cost and time to complete projects– Improve quality of data in resulting system
• Support application renovation projects– Dramatically reduce time and cost to complete– Improve quality of data in resulting system
• Support data integration functions for data warehousing/ business intelligence data stores
– Develop processes to cleanse data in transit– Improve quality of data in information intelligence stores
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Data Quality Program
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SvalTech
Data Profiling
Data Quality
Discovery
Data Quality
Correction
Data Quality
Prevention
Incident
Investigation
Name & Address
Cleansing
De-duplication
Re-verification
Data Quality
Monitoring
Business Process
Improvements
Application Software
Improvements
Data Quality Issue
Formulation &
Tracking
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Data Quality Discovery
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SvalTech
Data Profiling
Incident
Investigation
DATA profile DQ issues
Suspicion
Of DQ problem
profiler review
process
review
DATA DQ issues
review
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Data Profiling Functions
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SvalTech
• Column Examination– List all values in column with frequency of occurrence– Show high and low values– Determine true data type– Determine degree of uniqueness– Determine encoding patterns used, frequency of each pattern– Compute values: AVG, SUM, MEDIAN, STD DEVIATION
• Row Examination– Find all primary key candidates (single or multi-column)– Find intra-row column dependencies (find denormalization instances)– Find multi-column value relationships
• Value ordering rules• NULL value dependencies
• Multi-table Examination– Find matching columns across tables
• Match by column name, data type• Match by values
– Find primary/foreign key pairs (single and multi-column)– Determine 1-1, 1-M, 1-0, M-1, M-M, 0-1 rules– Find primary values not found in secondary tables
• Test User provided data rules
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Potential for Discovery of Value Problems
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SvalTech
missing & invalid
values
valid but wrong
values
correct values
errors that can be
found through
analytical techniques
errors that can be
fixed without
re-verification
values recorded
in a column of a
table
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What Types of Problems can be identified for values in a column?
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SvalTech
Invalid Values - missing values when should not be missing
- values out of range or not in domain of expected values
- value in one column not possible when combined with
values in one or more other columns
- obviously wrong when looked at•Name = Donald Duck•Address = 1600 Pennsylvania Avenue
Valid Values - distribution of values unexpected
too many of one or more values
too few of one or more values
- value is incompatible with other values in other columns
- multiple values mean same thing
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What Types of Problems can be Fixed?
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SvalTech
• Synonyms (multiple representations for same value)
• Multiple ways to express same value
•Date formats
•Number formats
•Use of case on character values
• Cases where the value of a column can be determined from the
values in one or more other columns
explicitly: through a rule
correlation against known combinations
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Role of Metadata and Data Rules
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SvalTech
• must define what constitutes correct
• traditional metadata is only part of definition
• traditional metadata is often inaccurate and/or incomplete
• data rules exist whether known or not
• data rules exist whether enforced or not
• profiling can validate metadata and known data rules
• can be used to correct or enhance metadata and data rules
• can be used to discover additional data rules
• can test adherence to data rules
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Data Profiling Solution Architectures
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SvalTech
metadata
data rules
data
extract
samples
gather metadata
& data rules
profilerprofile
reviewupdate metadata
and data rules
Identify and quantify problems
determine impact on business
create DQ problem tickets
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Solution Architectures
Copyright SvalTech, Inc., 2010
SvalTech
Home Grown Vendor Tools
Inefficient
Directed SQL; not generic
Easy Algorithms
Few Surprises uncovered
More sophisticated functions
third normal form discovery
foreign key discovery
multiple pattern recognition
More management of results
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State of Vendor Support
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SvalTech
• Fragmented– Different products call themselves data profiling but do different things– Some non-profiling products call themselves profiling
• Buried in multiple data management functions
• Marketed as compliance product
• Not a lot of advances in technology over last few years– More complex array of profiling functions– Targeted profiling functions– Menu of functions to pick from– SaaS– Profiling of metadata– Monitoring operational systems for profiling expectations
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Business Case Basics
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SvalTech
• Dollar savings– Fewer Operational Mistakes
• Reduced rework• Reduced customer returns
– Improved Analytic Results• Better decision making from Analytics
• Improved Operations– Fewer operational glitches due to wrong data values– Reduced time to complete projects
• Risk Reduction– Reduced exposure to catastrophic events– Reduced exposure to legal scrutiny of data
It’s all indirect:
you cannot determine
what value you will get
until after you have
profiled data, studied
results and used it to
some advantage.
Data Quality problems can cost
a company 15-25% of bottom line profit.
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How to Get Started
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SvalTech
• Need to establish as part of quality improvement/ compliance/ governance program
– 6 Sigma like– Multi-department interest
• Start with a pilot data quality assessment of a critical data resource– Small– Targeted: high value consequences of poor data– “see what we find”
• Possibly start with a renovation/ consolidation/ integration project– Process to establish source level metadata and understand data content
• Need to Quantify Results
• Use Success to Expand Use of Technology
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Why is it Neglected?
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SvalTech
• Problems are not on Top Ten List of IT Concerns
• Cannot predict value: cannot build business case in advance– Don’t know value of a data quality improvements until after you discover the problems– Value is hard to quantify: does not appear until quality problems acted upon
• Perception that you don’t need it
• Exposes corporate/ IT weaknesses
• No Clear Owner of Data Quality
• Lack of education on value, cost to implement– Management education– Technical Staff education
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Database Archiving
SvalTech
Copyright SvalTech, Inc., 2010
22
Books
Copyright SvalTech, Inc., 2010
SvalTech
• Database Archiving: How to Keep Lots of Data for a Very Long Time, Jack E. Olson, Morgan Kaufmann, 2009
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Definition
Document Archiving word pdf excel XML
File Archiving structured files source code reports
Email Archiving outlook lotus notes
Database Archiving DB2 IMS ORACLE SAP PEOPLESOFT
Physical Documents application forms mortgage papers prescriptions
Multi-media files pictures sound telemetry
The process of removing selected data items from operational databases that are not expected to be referencedagain and storing them in an archive database where they can be retrieved if needed.
SvalTech
Copyright SvalTech, Inc., 2010
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Business Records: the Archive Unit
SvalTech
You don’t archive databases; you archive data from databases.
A Business Record is the data captured and maintained for a single business event or to describe a single real world object.
Databases are collections of Business Records.
Database Archiving is Records Retention.
customer employee stock trade purchase order deposit loan payment
Copyright SvalTech, Inc., 2010
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Data Retention
SvalTech
The requirement to keep data for a business object for a specified period of time. The object cannot be destroyed untilafter the time for all such requirements applicable to it has past.
Business Requirements
Regulatory Requirements
The Data Retention requirement is the longest of all requirement lines.
Copyright SvalTech, Inc., 2010
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Data Retention
SvalTech
• Retention requirements vary by business object type
• Retention requirements from regulations are exceeding business requirements
• Retention requirements will vary by country
• Retention requirements imply the obligation to maintain the authenticity of the data throughout the retention period
• Retention requirements imply the requirement to faithfully render the data on demand in a common business form understandable to the requestor
• The most important business objects tend to have the longest retention periods
• The data with the longest retention periods tends to be accumulate the largest number of instances
• Retention requirements often exceed 10 years. Requirements exist for 25, 50, 70 and more years for some applications
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Where Database Archiving Is Used
SvalTech
Copyright SvalTech, Inc., 2010
• Overloaded Operational Databases
• Retired Applications
• Application Renovation Projects
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Overloaded Operational DatabasesSvalTech
• Transaction data• Lots of data
– Hundreds of millions of rows– High daily transaction rate
• 24/7 operational availability requirement• Long retention period (15 years or more) • Short useful active life (less than 2 years)• Low access requirements during the inactive period
– Very low access frequency– Response time not critical– Access requirements are simple, easily satisfied with ad hoc tools
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Retired ApplicationsSvalTech
• Merger of companies results in an operational application being duplicated
• Data Structures are not compatible– One keeps data elements not in other– One encodes data elements differently– One designed for different OS/DBMS than other
• Decision is made to use one system and abandon the other one
• Meets all characteristics of an operational application
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Application Renovation ProjectsSvalTech
• Application is undergoing major change– Replaced with packaged application– Legacy modernization– Legacy termination– Rewritten to be web-centric– Need to satisfy new requirements
• Old data structures are out of date– Legacy DBMS– Legacy file system
• Data meets all other requirements for archiving operational application
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Architecture of Database Archiving
Archive Server
Operational System
archive catalog
archive storage
OP DB
Archive AdministratorArchive DesignerArchive Data ManagerArchive Access Manager
SvalTech
Archive Extractor
Application program
Archive extractor
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Archive StaffSvalTech
• Database Archive Specialist– Received education on database archive design and implementation– Knows tools available– Experienced– Full time job
• Database Archive Administrator– Received education on database archiving administration– Full time job
• Supporting Roles– Storage Administrators– Database Administrators– Data Stewards– Security Administrators– Compliance staff– IT management– Business Unit Management– Legal– Records Management
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Archive Designer ComponentSvalTech
• Metadata– Capture current metadata– Validate it– Enhance it– Design archive storage format
• Data– Define business records to be archived– Define source of data– Define data structures within operational system– Define reference data needed to include with it– Define archive format of data
• Policies– Define extract policy (when a record becomes inactive)– Define operational disposal policy (when to remove from operational database)– Define storage policy (how to protect data in archive)– Define discard policy (when to remove from archive)
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Archive Extractor ComponentsSvalTech
• Extractor process– Verify consistency with design metadata– Extract data as defined in designer– Mark or delete from operational database as defined in designer– Pass data to archive data manager– Keep audit records on everything done– Do not impact operational performance– Support interruptions with transaction level recovery– Support restart– Finish scans within acceptable time periods
• Scheduling– Establish periodic executions– Find non-disruptive periods– Be consistent
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Archive ExtractorsPhysical vs. Application Extractors
SvalTech
Copyright SvalTech, Inc., 2010
Operational System
OP DB
Archive Extractor
Application program
Archive extractor
Physical ExtractorGets/deletes data directly from the database
tables, rows, columns
Application ExtractorGets/deletes data from an application API
virtual tables, rows, columns
application program
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Archive Data Manager ComponentSvalTech
• Put data away– Receive data from extractors– Format into archive segment files– Determine metadata version affinity– Format and store metadata files if new– Build or update segment indexes both internal and external
• Execute Storage policies– Encryption/ signatures– Backup copies created and stored– Geographic dispersion of backups– Register archive files with archive catalog– Enter audit trail information
• Fetch metadata on request– Return to accessing programs
• Fetch data on request– Scan archive segments– Search through indexes
• Execute Archive Discard Process– Periodic scheduling– Delete qualifying business records– Update archive catalog
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Archive Access ComponentSvalTech
• Query Capability– Determine applicability based on archive segment versions of metadata– SQL based is best, if possible– Employ external indexes to determine which archive segments to look into– Employ internal indexes to avoid reading all of an archive segment
• Support standard access tools– Report generation (such as Crystal Reports)– Generic query tools– JDBC interface
• Support metadata version browsing
• Support generation of load files based on query results
• Support generation of load files based on original data source based on query results
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Archive Administration ComponentSvalTech
• Manage Archive Catalog– Application archive designs– Audit trails– Results logs
• Manage Archive Storage Systems– Ensure periodic readability checks– Maintain access audit trails
• Manage Archive Access– Authorizations for users– Authorizations for specific events
• Unloads– Ensure audit records are created for all access
• Manage e-Discovery requests
• Ensure Extract and Discard processes are run when they are supposed to
• Manage Metadata Change Process
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SvalTech
Home-Grown Solutions:
Use Parallel DB Use Database Partitions Put in UNLOAD files Save Image Copies of DB
Copyright SvalTech, Inc., 2010
Solution ComparisonsHome-Grown vs. Vendor
Vendor Solutions:
More Complete Solutions Support Long Term Administration Put data in XML files Put data in reformatted files Exploit strengths of storage subsystems Direct access support
40
SvalTech
Copyright SvalTech, Inc., 2010
Home-Grown Solutions• Solve Operational Problems, BUT:
– Create downstream problems
– Fail to achieve cost savings
– Render archive data inaccessible
• Either completely or,
• Expensive in time and cost to query
– Lose data authenticity
• Common Omissions– No handling or improvement of metadata
– No change process for structure changes
– No long term storage management
– Fail to achieve application/system independence
– No administration platform
41
SvalTech
Copyright SvalTech, Inc., 2010
Vendor Solutions• Not a Lot of Vendors
– Only 7 I know of– 3 large companies
• Through acquisition– Gartner pre-recession characterization
• Is a new technology• $100M in 2008• 40% per year growth rate• Early adopter stage
• Solutions not complete– Need growth in function and maturity– Common weak spots
• Design modeling• Extractor technology• Not pervasive across data sources• Storage structure• Storage management
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Business Case BasicsDrivers
SvalTech
overloadedoperationaldatabases
Longer Data Retention requirements
Expanded Business
Mergers and Acquisitions
Copyright SvalTech, Inc., 2010
Operational problems
Data Governancee-Records Retentione-Discovery Readiness concerns
Difficulty in Making Application Changes
Cost of Keeping Old Systems
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Reason for Archiving
Operational operational archive
All data in operational db
most expensive system most expensive storage most expensive software
Inactive data in archive db
least expensive system least expensive storage least expensive software
In a typical op db60-80% of datais inactive
This percentageis growing
SvalTech
Size Today
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Cost Saving ElementsSvalTech
Copyright SvalTech, Inc., 2010
Look for and compute difference in storage costs
front-line vs archive storage
byte counts differences between operational and archive
Look for and compute difference in system costs
operational vs archive systems
are operational system upgrades avoided
are software upgrades avoided
can systems be eliminated for application
can software be eliminated for application
Look for savings on people costs
can people be eliminated or redirected for retired applications
Potential savings on changes/ application renovations
simplification of design
elimination of data conversions
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Operational Efficiency ImpactsSvalTech
Copyright SvalTech, Inc., 2010
Will operational performance be enhanced with less data
Will utility time periods be reduced (backup, reorganization)
fewer occurrences needed
less data to process each time
Will recovery times be reduced and what is that worth
interruption recoveries
disaster recoveries
Will implementation of data structure changes be improved
avoided
reduced amount of data to unload/modify/reload
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Risk FactorsSvalTech
Copyright SvalTech, Inc., 2010
Will the saved data have better authenticity
not changed in archive
shielded from updates or damage
traceable back to original form
Will e-Discovery benefit from archiving
can locate and process data outside of operational environment
can easily create legal-hold archive units
Will exposure of data reduced
fewer authorized users against the archive
complete audit trails of all access
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Business Case SummarySvalTech
Copyright SvalTech, Inc., 2010
• Database Archiving solutions generally provide for lower cost software,
can use lower cost storage more efficiently, and run on smaller machines.
• Each business case is different
Many factors can be used in building business case
Seen an application justified on storage costs alone
Seen an application justified on disaster recovery time alone
Seen an application justified on better data security alone
• Each organization will have many potential applications
• Having a database archiving practice can create synergies across many
applications thus adding more value
48
Why is it Neglected?
Copyright SvalTech, Inc., 2010
SvalTech
• Belief that work arounds are good enough
• Technology is too new
• Technology is incomplete or flawed
• Inability to produce complete business case to justify
• Lack of experience in using technology
• Lack of education on value, cost to implement– Management education– Technical Staff education
49
Final ThoughtsSvalTech
Copyright SvalTech, Inc., 2010
Are these two technologies related?
Enterprises who consider data a critical and valuable asset and who have a goal
of collecting, protecting, preserving and deploying data to the best advantage
of the enterprise WILL have robust data management and data governance practices.
These will include professional management of:
- data and metadata architectural control
- active and ongoing data quality improvement program
- active and ongoing data archiving program (records management)
- data security control
- access authorization and auditing
- data encryption
- data protection program
- backups
- disaster recovery
- protection from unauthorized access/ changes
- data distribution control