Consider the General Hardware Corp. database of Figure 6.1. Describe the problem of referential integrity in terms of the CUSTOMER and CUSTOMER EMPLOYEE relations if the record for customer 2198 in the CUSTOMER relation is deleted. (Assume that no delete rules exist.)

(d) PRODUCT relation Salesperson Number (a) SALESPERSON relation Salesperson Commission Name Percentage Year of Hire Office Number Product Number Product Name Unit Price 10 15 137 186 204 361 Baker Adams Dickens Carlyle 1995 2001 1998 2001 1284 1253 1209 1227 16386 19440 21765 24013 26722 Wrench Hammer Drill Saw 10 20 12.95 17.50 32.99 26.25 11.50 Pliers (b) CUSTOMER relation (e) SALES relation Customer Number Customer Name Salesperson Number HQ City Salesperson Number Product Number Quantity 137 186 137 137 0121 0839 0933 1047 1525 1700 1826 2198 2267 Main St. Hardware Jane's Stores ABC Home Stores Acme Hardware Store Fred's Tool Stores XYZ Stores City Hardware Western Hardware Central Stores 361 New York Chicago Los Angeles Los Angeles Atlanta Washington New York New York New York 361 137 204 186 137 137 137 186 186 186 186 204 204 361 361 361 19440 24013 26722 16386 19440 21765 24013 21765 26722 16386 21765 26722 473 170 688 1,745 2,529 1,962 3,071 809 734 3,729 3,110 2,738 (c) CUSTOMER EMPLOYEE relation Customer Number Employee Number Employee Name Title (f) OFFICE relation Office Number Telephone Size (sq. ft.) 0121 0121 0933 0933 0933 1525 2198 2198 2198 2198 27498 30441 25270 30441 48285 33779 27470 30441 33779 35268 Smith Garcia Chen Levy Morton Baker Smith Jones Garcia Kaplan Co-Owner Co-Owner VP Sales Sales Manager President Sales Manager President VP Sales VP Personnel Senior Accountant (Continues) 1253 1227 1284 1209 901-555-4276 901-555-0364 901-555-7335 901-555-3108 120 100 120 95