about metadata

1. Introduction about
metadata

2. Contents
 Definition
 Types of metadata
 Roll of metadata
 Challenges of metadata

3. Definition
 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.

4.  Created for the data names and
definition of a given 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.
 Index of a book work like metadata of
content of book.

5. Types of metadata
It is broadly categories into three
types.
1. Business metadata
2. technical metadata
3. Operation metadata

6. Business metadata
 Contains the data ownership
information,.
 Business definition
 Changing policies.
 Source system name and discription
 Report name and discription
 Obtained from business users

7. Operation metadata
 It include currency of data and data
lineage.
 Currency of data means whether the
data is active ,achieved or purged.
 Lineage of data means the history of
data migrate and transformation on it

8. Technical metadata
 Includes database system names,
table and column names and size,
data types and allowed values.
 Includes structural information such as
primary key and foreign key attribute
and indices.

9. Role of metadata
 Act as directory.
 Directory helps decision support
system to allocate the content of data
warehouse.
 Helps in mapping of data when data
transformed from operational
environment to data warehouse
environment.

10.  Helps in summarization between
current detailed data and highly
summarized data.
 used as query tools
 Used as reporting tools.
 Used as extraction and cleaning
tools.

11. Challenges of metadata
 Stores data is correctly
defined for further uses.

12. thanks