Data base design Essay Example | Topics and Well Written Essays - 1000 words

Data base design - Essay Example ReqLayout EquipmentType Room Roomno (PK) Name (Room Name or Eating area description) Roomtype (Conf. Or Eating) Capacity Costpersession Openfor RefreshmentMealDetail OrgCode (PK) RMdate (PK) (where RM is refreshment and Meal) RMtime (PK) Roomno/Mealroom (PK) OrderId (PK) Ordertype (refreshment / meal) Quantity Order OrderId (PK) Description (beverage name, lunch, dinner, evening) 3NF Eliminate columns not dependent on the key. If attributes do not contribute to a description of the key, remove them to a separate table. All non-key fields must be exclusively dependent on the key field. Over here all tables in 2NF are already in 3NF as follows: Organization Orgcode (PK) OrgName OrgAddress OrgPostcode OrgContact OrgTel OrgFax OrgEvent NosExpected Booking OrgCode (PK) BookDate (PK) Roomno (PK) Session (PK) ReqLayout EquipmentType Room Roomno (PK) Name (Room Name or Eating area description) Roomtype (Conf. Or Eating) Capacity Costpersession Openfor RefreshmentMealDetail OrgCode (PK) RMdate (PK) (where RM is refreshment and Meal) RMtime (PK) Roomno/Mealroom (PK) OrderId (PK) Ordertype (refreshment / meal) Quantity Order OrderId (PK) Description (beverage name, lunch, dinner, evening) 4NF Isolate independent multiple relationships. No table may contain two or more 1:n or n:m relationships that are not directly related. All tables which are in 3NF are already in 4NF except "Booking" table. Organization Orgcode (PK) OrgName OrgAddress OrgPostcode OrgContact OrgTel OrgFax OrgEvent NosExpected Booking OrgCode (PK) BookDate (PK) Roomno (PK) Session (PK) Layoutid EquipId Layout Layoutid (PK) Description Equipment EquipId (PK) Description Room Roomno (PK) Name (Room Name or Eating area description) Roomtype (Conf. Or...All non-key fields must be exclusively dependent on the key field. Over here all tables in 2NF are already in 3NF as follows: Isolate independent multiple relationships. No table may contain two or more 1:n or n:m relationships that are not directly related. All tables which are in 3NF are already in 4NF except "Booking" table. Isolate semantically related multiple relationships. There may be practical constraints on information that justify separating logically related many-to-many relationships. All tables in 4NF are already in 5NF except "Room" table.