Agenda 02/21/2013

Discuss exerciseAnswer questions in task #1

Put up your sample databases for tasks #2 and #3

Define ETL in more depth by the activities performed.

Discuss the “controversy” in ETL activities

Discussed in prior classes...

Lots of data.Traditional transaction processing systems

Non-traditional transaction processingCall center; Click-stream; Loyalty card; Warranty cards/product registration information

External data from government and commercial entities.

Lots of poor quality data for lots of reasons that can be traced back to lots of people.

Master Data Management: What does it mean and why is it so difficult to manage

master data?

Populating the data warehouse

ExtractTake data from source systems. May require middleware to gather all necessary data.

TransformationPut data into consistent format and content.Validate data – check for accuracy, consistency using pre-defined and agreed-upon business rules.Convert data as necessary.

LoadUse a batch (bulk) update operation that keeps track of what is loaded, where, when and how. Keep a detailed load log to audit updates to the data warehouse.

Data Cleansing

Source systems contain “dirty data” that must be cleansed

ETL software contains rudimentary to very sophisticated data cleansing capabilities

Industry-specific data cleansing software is often used. Important for performing name and address correction

Leading data cleansing vendors include general hardware/software vendors such as IBM, Oracle, SAP, Microsoft and specialty vendors Information Builders (DataMigrator), Harte-Hanks (Trillium), CloverETL, Talend, and BusinessObjects (Centric)

Steps in data cleansing

· Parsing

· Correcting

· Standardizing

· Matching

· Consolidating

Parsing

Parsing locates and identifies individual data elements in the source files and then isolates these data elements in the target files.

Examples include parsing the first, middle, and last name; street number and street name; and city and state.

Input Data from Source FileBeth Christine Parker, SLS MGRRegional Port AuthorityFederal Building12800 Lake CalumetHedgewisch, IL

Parsed Data in Target FileFirst Name: BethMiddle Name: ChristineLast Name: ParkerTitle: SLS MGRFirm: Regional Port AuthorityLocation: Federal BuildingNumber: 12800Street: Lake CalumetCity: HedgewischState: IL

Parsing

Correcting

Corrects parsed individual data components using sophisticated data algorithms and secondary data sources.

Correcting

Corrected DataFirst Name: BethMiddle Name: ChristineLast Name: ParkerTitle: SLS MGRFirm: Regional Port AuthorityLocation: Federal BuildingNumber: 12800Street: South Butler DriveCity: ChicagoState: ILZip: 60633Zip+Four: 2398

Parsed DataFirst Name: BethMiddle Name: ChristineLast Name: ParkerTitle: SLS MGRFirm: Regional Port AuthorityLocation: Federal BuildingNumber: 12800Street: Lake CalumetCity: HedgewischState: IL

Standardizing

Standardizing applies conversion routines to transform data into its preferred (and consistent) format using both standard and custom business rules.

Standardizing

Corrected DataFirst Name: BethMiddle Name: ChristineLast Name: ParkerTitle: SLS MGRFirm: Regional Port AuthorityLocation: Federal BuildingNumber: 12800Street: South Butler DriveCity: ChicagoState: ILZip: 60633Zip+Four: 2398

Corrected DataPre-name: Ms.First Name: Beth1st Name Match Standards: Elizabeth, Bethany, BethelMiddle Name: ChristineLast Name: ParkerTitle: Sales Mgr.Firm: Regional Port AuthorityLocation: Federal BuildingNumber: 12800Street: S. Butler Dr.City: ChicagoState: ILZip: 60633Zip+Four: 2398

Matching

Searching and matching records within and across the parsed, corrected and standardized data based on predefined business rules to eliminate duplications.

Matching

Corrected Data (Data Source #1)Pre-name: Ms.First Name: Beth1st Name Match Standards: Elizabeth, Bethany, BethelMiddle Name: ChristineLast Name: ParkerTitle: Sales Mgr.Firm: Regional Port AuthorityLocation: Federal BuildingNumber: 12800Street: S. Butler Dr.City: ChicagoState: ILZip: 60633Zip+Four: 2398

Corrected Data (Data Source #2)Pre-name: Ms.First Name: Elizabeth1st Name Match Standards: Beth, Bethany, BethelMiddle Name: ChristineLast Name: Parker-LewisTitle: Firm: Regional Port AuthorityLocation: Federal BuildingNumber: 12800Street: S. Butler Dr., Suite 2City: ChicagoState: ILZip: 60633Zip+Four: 2398Phone: 708-555-1234Fax: 708-555-5678

Consolidating

Analyzing and identifying relationships between matched records and consolidating/merging them into ONE representation.

Consolidating

Corrected Data (Data Source #1)

Corrected Data (Data Source #2)

Consolidated DataName: Ms. Beth (Elizabeth) Christine Parker-LewisTitle: Sales Mgr.Firm: Regional Port AuthorityLocation: Federal BuildingAddress: 12800 S. Butler Dr., Suite 2 Chicago, IL 60633-2398Phone: 708-555-1234Fax: 708-555-5678

Source system view – 3 clients

Policy No.ME309451-2

Account#1238891

TransactionB498/97

The reality – ONE client

Account#1238891

Policy No.ME309451-2

TransactionB498/97

Consolidating whole groups

William Parker

BethLewis

Karen Parker-Lewis

William Parker-Lewis, Jr.

ETL Products

SQL Server 2012 Integration Services from Microsoft

Power Mart/Power Center from Informatica

Warehouse Builder from Oracle

Teradata Warehouse Builder from Teradata

DataMigrator from Information Builders

SAS System from SAS Institute

Connectivity Solutions from OpenText

Ab Initio

What about unstructured data?

What is unstructured data?

What percentage of data in organizations is considered to be “unstructured”?

Examples

Why store it in a data warehouse?

Does it do any good in large text fields?

Special ETL for unstructured data

Unstructured Data Example

Notes about post-service of a product:The hub bent when the bicycle hit a large pothole.

The plane takes off sluggishly during high-altitude departures.

The product won’t allow entry of a 1098-T when the person is declared as a dependent.

“Text analytics” are used to transform the data.

Text analytics

Parses text and extracts facts (complaints, problems, issues) about key entities (customers, products, locations).

Uses natural language processes (NLP).NLP converts human language into more formal representations that are easier for a computer program to manipulate.

Combination of computational linguistics and artificial intelligence.

Goal of ETL

Structured and unstructured data stored in a relational database.

Data is complete, accurate, consistent, and in conformance with the business rules of the organization.

Controversy in ETL

Is it necessary?

Has the advent of big data changed our need for ETL?

ETL vs. ELT

Does the use of Hadoop eliminate the need for ETL software???