TA Ch3 - Chapter 3: The Relational Database Model 3. Why...

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Chapter 3: The Relational Database Model 3. Why are entity integrity and referential integrity important in a database? Entity integrity and referential integrity are important in a database because if a database does not have these two attributes, then the database could not work properly and put out wrong or misleading information. 17. Identify and describe the components of the table shown in Figure Q3.17, using correct terminology. Use you knowledge of naming conventions to identify the table's probable foreign key(s). EMP_NUM -- primary key, candidate key, superkey EMP_LNAME, EMP_FNAME -- foreign key EMP_LNAME, EMP_INITIAL, EMP_FNAME -- secondary key Problems: 17. For each table, identify the primary key and the foreign key(s). If a table does not have a foreign key, write None in the space provided. TABLE PRIMARY KEY FOREIGN KEY(S) TRUCK TRUCK_NUM BASE_CODE, TYPE_CODE BASE BASE_CODE NONE TYPE TYPE_CODE NONE 18. Do the tables exhibit entity integrity? Answer yes or no, and then explain your
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This note was uploaded on 07/13/2011 for the course IST 210 taught by Professor Mcconn,charlotteryoo,jungwoo during the Summer '08 term at Penn State.

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TA Ch3 - Chapter 3: The Relational Database Model 3. Why...

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