Find the names of all brokers who have made money in all accounts assigned to them.
Write the query of Exercise 5.22 using TRC and DRC.
a. TRC:
{B.Name | Broker(B) AND
?A ? Account (A.BrokerId= B.Id ? A.Gain> 0)
b. DRC:
{Name |?BrokerId (Broker(BrokerId, Name) AND
?Acc# ?Gain (Account(Acc#, BrokerId, Gain) ? Gain> 0 )) }
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The primary purpose for decreasing user privilege levels is:
a. To reduce support costs b. To limit the effects of malware c. To improve system performance d. All of the above
If unexpected data is processed in an I/O operation:
a. An exception will be thrown. b. An error message will automatically be displayed. c. The program will terminate execution. d. Various error bits will be set.
The choice to enforce referential integrity is indicated in Design view by a thick ____
A. border around the table name B. border around the primary key of the primary table C. join line D. red join line
The size of the ____, border, and margin all increase the amount of space on a web page that an element occupies or influences.
A. picture B. frame C. style D. padding