Metadata in data warehouse

metadata in datawarehouse

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