powerpoint about metadata

1. Metadata
In
Data Warehouse
Made By: Supervisor:
Noor Hamad Dr.Murtadha

2. Metadata information that describes data is the Basis of
all information management For the purpose of
increasing efficiency in the organizations. Metadata
plays an important role and provides the foundation for
all actions in all stages on data warehouse.
This paper different definition of Metadata and
historical background are found and discuss why
Metadata is important and list the categories of
Metadata and example about import source Metadata
from file in data warehouse.

3. Data warehouse metadata are pieces of information
stored in one or more special-purpose metadata
repositories that include
(a) information on the contents of the data warehouse,
their location and their structure
(b) information on the processes that take place in the
data warehouse back-stage
(c) information on the implicit semantics of data (with
respect to a common enterprise model)
, (d) information on the infrastructure and physical
characteristics of components and the sources of the data
warehouse,
(e) information including security, authentication, and
usage statistics that aids the administrator tune the
operation of the data warehouse as appropriate.

4. Some researchers point out that the term began to appear
clearly in the intellectual production of database management
systems in the 1980s, and that the use of the term metadata by
computer scientists was to describe the information required to
document the characteristics of information contained in
database management systems, Because the computer
represented the surrounding for the data being described and
the descriptive data itself is simply defined as data about data,
and although Metadata does not exclude non-electronic data, it
often applies to data in its electronic form.
The developments of the 1990s linked to the existence of an
enormous amount of information on the Internet led to the
need for a standardized of Internet resources so that the most
useful available information could be discovered to meet our
information needs, Metadata to indicate information about a
source.

5. Metadata is data in data warehouse, to represent
other data. Or, metadata is data about data.
It is summarized data that leads to detailed data.
It roadmap about data warehouse.
Act as a directory to helps the decision support
system to locate the content of a data warehouse.
In data warehouse defines the warehouse object.

6. 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.

7. For building the data warehouse
Need to know the structure and data content
in the data warehouse. Mapping and data
transformations. Logical structure of data
warehouse database

8. 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

11. Metadata
Categories
Operational
Metadata
Technical
Metadata
Business
Metadata

12. Metadata can be broadly categorized into three categories:
Business Metadata - It has the data ownership
information, business definition, and changing policies.
Technical Metadata - It includes database system names,
table and column names and sizes, data types and allowed
values. Technical metadata also includes structural
information such as primary and foreign key attributes
and indices.
Operational Metadata - It includes currency of data and
data lineage. Currency of data means whether the data is
active, archived, or purged. Lineage of data means the
history of data migrated and transformation applied on it.

13. In this example show how to import source Metadata from file
in data warehouse:
First open Oracle warehouse Builder

15. Put it in folder and save it in .csv extension

24. Metadata is "data about data" pertaining to
data warehouse this information is used to
facilitate the query within the data
warehouse and to speed the response