Dependency

Any database can have many inter-relationships between objects and some of these relationships can be quite distant.

For example a View has a dependency on any tables that make up the view and this is especially critical if the view is Schema Bound. A foreign key creates a dependency between two tables.

SQL Delta reads both the SQL Server dependency data found in the catalog view such as sys.sql_expression_dependencies as well as decoding the various objects and mapping the dependencies.

In the example of comparing into an empty database a view must be created after the table it references has been created. SQL Delta evaluates the database dependency map and automatically orders the script so tables are created before views.

In a complex scenario a table may rely upon a function and that function relies upon a view which relies on a table and so on. In this instance the script ordering is not as simple as sorting all the tables to the front of the script and the views to the end. 

Dependency Mapping not Wanted

There can be instances where you wish to update a single item within a schema compare containing many differences. This can be done by selecting the object to update and de-selecting all other updatable objects. By default SQL Delta will review your selection and then automatically add object the single update requires. or may require. In some cases these additions are not wanted. The No Depend button will cancel to dependency mapping and only script the objects you select to script. Of course if you select a view to be updated and the corresponding table does not exist then the view will not successfully update.