Thursday, December 12, 2019

Information Systems free essay sample

Courses (Course ID, CourseName) b) For each of the tables you created, what are the candidate keys? There are Students Table and Courses Table. Students Table: Candidate keys include student ID, firstName and lastName. Courses Table: They candidate key is the Course ID and courseName. c) For each of the tables you created, what is the primary key? The primary key of Students Table is Student ID. The primary key of Courses Table is Course ID. d) Explain how the two tables are related. Which table contains the foreign key? What is the foreign key? The students and their course names make the tables related. The student ID correlates to the students last names and first names and the course ID. Therefore, this is the primary key. The course ID is the foreign key of the Course Table. 2) The Cape Codd Outdoor Sports database has the following tables: RETAIL_ORDER (OrderNumber, StoreNumber, StoreZip, OrderMonth, OrderYear, OrderTotal) ORDER_ITEM (OrderNumber, SKU, Quantity, Price, ExtendedPrice) SKU_DATA (SKU, SKU_Description, Department, Buyer) WAREHOUSE (WarehouseID, WarehouseCity, WarehouseState, Manager, Squarefeet) INVENTORY (WarehouseID, SKU, SKU_Description, QuantityOnHand, QuantityOnOrder) a) There is a flaw in the design of the INVENTORY table. We will write a custom essay sample on Information Systems or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page Explain what this design flaw is. There are 2 primary keys in the inventory table, which are the Warehouse ID and the SKU. They are primary key references for relationships to other tables. b) For each of the tables above, what is the primary key? Retail_Order: Order Number Order_Item: Order Number SKU_Data: SKU Warehouse: Warehouse ID Inventory: Warehouse ID and SKU c) Which tables contain foreign keys? What are the foreign keys? Order_Item table contains a foreign key and the foreign keys are the SKU attribute. 3) We know that if a table meets certain requirements, it is considered a relation. Give three examples of tables that are not relations. Explain why they are not relations. In a column, entries have to be the same kind or else the data would not be consistent. Every row must be different because 2 of the same kind would not be consistent. A table that has more than one identical column name would not be a relation because it is confusing to know where to place data into a table.

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