When you update a parent table in a database, erwin Data Modeler may choose to implement the change by dropping and recreating the table. When erwin Data Modeler drops and recreates a table, it must also drop and recreate all dependent foreign keys in all child tables to maintain database integrity.
erwin Data Modeler automatically tracks and recreates all foreign key dependencies for a dropped table if you are comparing a model with an existing database. All affected child tables are also included in the Resolve Differences list.
erwin Data Modeler can only drop and recreate the foreign key dependencies if it can find them in the database or the Resolve Differences list. If you are comparing a model to a SQL script file or erwin Data Modeler model and a child table with a dependent foreign key is not included in the compare, erwin Data Modeler cannot find and maintain the foreign key dependencies.
To properly maintain database integrity, if you are comparing a model with a SQL script or .erwin file, you should verify that all dependent tables are included in the Differences list.
If you modify a table that is referenced by stored procedures, triggers, and views, the referencing items may be invalidated or dropped (for DB2 z/OS, and some other databases) depending on the type of modification. erwin Data Modeler does not recompile or recreate these items automatically.
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