Meta Data
There is one more significant factor in the flow of data through an organization. You have to understand what is happening to the data as all these transformations are taking place.
Meta data is data about data—the information that people need to know about the data they are using. Meta data answers the following questions:
-
What is the source of this data?
-
What is the meaning of this particular piece of data?
-
What are the data types used to store this data?
-
What data transformations were used on this data?
-
When was this data transformed?
-
Who is responsible for maintaining this data?
-
Who has permission to access this data?
-
How reliable is this data?
Meta data is important at every point in the enterprise data structure. It provides information about the sources of data, the data transformation processes, and the current location of the data. It provides information to the data transformation tools and to the users of the data. Figure 3.7 shows the place of meta data in the flow of data through the enterprise.
){kind=link}
Figure
3.7
Meta data is essential throughout the data transformation process.
Microsoft has included a tool called Meta Data Services with SQL Server 2000. This tool is integrated with Data Transformation Services to provide information about the data in the databases and the transformations that are used to modify that data.
The use of meta data is described in Chapter 29, "Integrating DTS with Meta Data Services."
Note - Many people use "metadata" as one word, but in SQL Server 2000 Books Online it's two words. What is called Meta Data Services in SQL Server 2000 was referred to as the Repository in SQL Server 7. The term "repository" is still used to describe the place where Meta Data Services stores the meta data.