THE SIGNIFICANT ROLE THE SIGNIFICANT ROLE OF METADATAOF METADATA

WHY METADATA IS IMPORTANT

• Metadata in a data warehouse contains the answers to questions about the data in the data warehouse.

• sample list of definitions:– Data about the data– Table of contents for the data– Catalog for the data– Data warehouse atlas– Data warehouse roadmap– Data warehouse directory– Glue that holds the data warehouse contents together– Tongs to handle the data– The nerve center

Ex : Use of metadataEx : Use of metadata• which territories does region “SOUTH”

include? • does the data item 04-01-2000 denote

April 1, 2000 or January 4, 2000? What is the convention used for dates in your data warehouse?

• Are the numbers shown as sale units given in physical units of the products, or in some measure such as pounds or kilograms?

• What about the amounts shown in the result set? Are these amounts in dollars or in some other currency?

• Metadata gives your user the meaning of each data element.