Metadata contains answers to questions about the data in a data warehouse. It is stored in a metadata repository and describes pertinent details about the data to users, developers, and the project team. Metadata is necessary for using, building, and administering the data warehouse as it provides information about data extraction, transformations, structure, refreshment, and more. It serves important roles for both business users and IT staff across the data acquisition, storage, and delivery processes.

1. Role of Metadata

2. Why Metadata
 Before touches the keyboard by the
prominent(superlative) users.
 Several questions come to their mind.
What are various data in the data
warehouse?
Is there information about unit sale and
costs by product?
How old is the data in the warehouse.
When was the last time fresh data was
brought in?
Are there any summaries by month and
product?

3. Why Meta data contd.,
 These questions and several more
information are very valid and pertinent.
 What are answers? Where are the
answers? Can ur user see the answers?
How easy to get the answers?

4. What is Meta data?
 Metadata in a data warehouse contains
the answer to questions about the data
in the data warehouse.
 Keep the answer in a place called the
metadata repository.

5. Different definitions for
metadata
 Data about the data.
 Table of contents for the data.
 Catalog for the data.
 Data warehouse roadmap.
 Data warehouse directory.
 Tongs to handle the data.
 The nerve center.

6. So, what exactly is metadata
 It tells u more.
 It gives more than the explanation of the
semantics and the syntax.
 Describes all the pertinent(relevant)
aspect of the data in the data
warehouse.
 Pertinent to whom?
 The answer is – primarily to the user
and also developer and even project
team.

7. Meta data

8. Why it is important?
 Metadata is necessary for using,
building and administering your data
warehouse.

9. For using the data warehouse
 Without the metadata support, user
cannot get an information every time
they needed(user create their own ad
hoc report).
 Today data warehouses are much larger
in size, wide in scope.
 User critically need metadata.

10. For building the data
warehouse(extraction team)
 Need to know the structure and data
content in the data warehouse.
 Mapping and data transformations.
 Logical structure of data warehouse
database.

11. For administering the data
warehouse
 Impossible to administer the data
warehouse(size)
 Large no of questions and queries.
 Cannot administer without answers for
these questions.
 Metadata must address these issues.

12. List of questions relating to
data warehouse

13. Who needs metadata?
 Without metadata, Datawarehouse is
like such a filling cabinet without
information.
 Go through the image column(it address
the our question)

15. Like a nerve center
 Metadata placed in a key position and
enables communication among various
processes.

17. Why metadata is essential for
IT
 Development and deployment of data
warehouse is joint effort between users
and IT staff.
 Technical issue-IT primarily responsible
design and ongoing administration.
 Metadata essential for IT
 beginning with the data extraction and
ending with information delivery.
 It drives and record the each processes.

19. Summary list of process in which
metadata is significant for IT
 Data extraction
 Data transformation
 Data scrubbing
 Data staging
 Data refreshment
 Database design
 Query report and design

20. Automation of DWH tasks

21. Types by Functional Area
 Classify and group in various way-some
by usage and who use it
 Administrative/End-user/Optimization
 Technical/Business
 Development/usage
 In the data mart/At the workstation
 Bank room/front room
 Internal/External

22. Functional Areas
 Data Acquisition
 Data stroage
 Information delivery

23. Data Acquisition
 DWH process related to following
functions.
Data extraction
Data transformation
Data cleaning
Data integration
Data staging

24. Data aquisition

25. Data stroage
 Data loading
 Data archiving
 Data management
 Use metadata in this area for full data
refresh and load.

27. Information Delivery
 Report generating
 Query processing
 Complex analysis
Mostly this are meant for end-user.
Metadata recorded in processes of other
two areas.
It also record OLAP-the developer and
administrators are involved in this
processes.

29. Business METADATA
 It connect business with DWH.
 Business users need more than other
users.
 Business metadata is like a roadmap.
 Tout guide-managers and analysis.

30.  Must describe the contents in plain
language giving information in business
teerms.
 Example
The name of data tables (or) individual
element must not be cryptic.
The data item name-calc_pr_sle.
You need to rename this as calculated-prior-
month-sale

31. Business metadata Contd.,
 Much less structured than technical
metadata.
 Textual documents, spreadsheets, and
even business rules and policies not
written down completely.

32. Examples of Business
Metadata who Benefits?
 Primarily benefits end-users.
Managers
Business analysis
Power users
Regular users
Casual users
Senior managers/ junior managers

33. Technical Metadata
 IT staff- Development and
Administration of the data warehouse.
 Who Benefits?
Project manager
Data warehouse administrator
Metadata manager
Database administrator
Business analyst
Data quality analyst