If you create an auto-incremented column or a sequence attached to a column, and then decide to change the target DBMS various transformations will be effected.
| 
                             DBMS change  | 
                        
                             Defined in original DBMS  | 
                        
                             Effect on sequence objects and auto-incremented columns  | 
                    
|---|---|---|
| 
                             DBMS supporting sequences to a DBMS supporting auto-incremented columns  | 
                        
                             Sequence attached to a column  | 
                        
                             The sequence disappears and the column to which it was attached becomes an auto-incremented column in the DBMS  | 
                    
| 
                             DBMS supporting auto-incremented columns to a DBMS supporting sequences  | 
                        
                             Auto-incremented column  | 
                        
                             The auto-incremented column is deleted and replaced by a sequence object called S_TABLENAME which is attached to the original column  |