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Cascade) of enforcing each of the violated constraint. For example, say, if you have one violated (referential integrity) constraint, you write down maximum, the 5

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Cascade) of enforcing each of the violated constraint. For example, say, if you have one violated (referential integrity) constraint, you write down maximum, the 5 different actions applying to this violation, explaining how each action is to be applied to this violation (i.e., at maximum, 5 explanations, totally). For another example, say, if you have two violated (referential integrity) constraints, you write down at maximum, the 4 different actions applying to each of the 2 violations, explaining how each action is to be applied to the respective violation (i.e., at maximum. 2 violations * 5 possible actions each = 10 explanations, totally). Etc., for three violated constraints, and so on. Notice that there are four relational constraints in the relational data model: domain constraint, key constraint, entity integrity constraint, referential integrity constraint. For each operation, you need to check for violation of each of the four constraints (not all of the constraints will be violated, just some of them but you need to check all of them to be sure which ones are violated, if any, otherwise you may overlook for some of the violations). For that, you need also to use the COMPANY database state in Figure 3.6 on p. 72 of the Elmasri's textbook; this Figure 3.6 is also shown in the lecture notes) [For the format of answering this question, you need to look in the examples of violations of constraints on p. 76, 77, and 78 in the Elmasri's textbook (6/E) and answer here in THE SAME manner and format. Also you may consult the Ch. 3 lecture notes, pages 15-17) 2. (23 pts - 8 pts PKs & 5x 3 - 15 pts FKs) Consider the following six relations for an order-processing database application in a company: CUSTOMER (Cust#, Cname, City) ORDER (Order#, Odate, Custo, Ord Amt) ORDER_ITEM (Order#, Itemt, Qty) ITEM (Itemi, Unit_price) SHIPMENT (Ordert, Warehouset, Ship_date) WAREHOUSE (Warehouset, City) Here, Ord Amt refers to total dollar amount of an order: Odate is the date the order was placed; Ship_date is the date an order is shipped from the warehouse. Assume that an order can be shipped from several warehouses. a. (8 points) Underline the primary keys in each relation. b. (15 points) Specify foreign keys for this schema, stating any assumptions you make. To do this, use the notation SHOWN in the following example: ORDER.Custno CUSTOMER Here, custno in the ORDER relation is a foreign key and it refers IMPLICITLY to the primary key Custno in the CUSTOMER relation). 3. (8 points) Write down short answer to the following: When you implement a DB (say COMPANY DB) in SQL, YOU MUST choose only one of these actions for each fk

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