Building SQL Server data dictionaries with extended properties and Third-party tools

A data dictionary is a collection of related descriptions of data and objects in a data model that helps programmers and users look up data and objects when they create applications and reports. When you use the data model, it is ideal to create a data dictionary. When databases are very small, developers often use Embedded SQL Server tools and scripts to create data models. But when the database model becomes an enterprise-class data model and has the corresponding complexity, the complexity of management and maintenance increases. So what can be done to manage and create such a data model? Is there any Third-party tool available?

To date, most data modeling tools use the same method to store data dictionaries. Some tools may use different terminology and more functionality, but essentially, the underlying technology is the same. This fundamental technique is a set of SQL Server extended properties that have been in use for a long time and are also supported in SQL Server 2008. There may be some changes in SQL Server 2011, but I believe there is an easy workaround if they are not fully supported.

In this article, you will not list in detail what the extended attributes are and how to add/Create/Update extended properties.

As mentioned earlier, when you use an enterprise-level data modeling, you tend to use third-party tools to manage this model. These tools have the ability to reverse engineer data graphs and data dictionaries, and to push the forward engineer model to the SQL Server database.

Extended properties from SQL Server 2000 are available. If you add an extended attribute using SQL Server Enterprise Manager, the name of the extended property is "Ms_description" in these system tables. Refer to the two graphs below as a reference point.

SQL Server 2000 table-level extended properties-look at the tagged description area

Figure 1

SQL 2000 Field level – see description

Figure 2

As you can see, none of the names in SQL Server 2000 is defined in those descriptions. However, if you use SQL Server Management Studio or an updated version, the name and value will be defined as follows:

SQL 2005/2008 Tool Table level

Figure 3