How has the differences between programming languages and database languages driven the trend to a multilayer design?
One of the problems with object-oriented programs that use databases is a slight mismatch between programming languages and database Structured Query Language (SQL) statements. In a database, tables are linked through the use of foreign keys and data is obtained through a relational join. However, in OO programming languages, references are made to objects in memory to obtain data. Therefore, the design, programming, and maintenance in a system is easier if separate classes are defined to access the database and get the data in a form that is conducive to processing in the computer. Rather than mix the business logic with the data access logic, it is better to define separate classes and let each focus on its primary responsibility.
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Which two of the following are NOT challenges posed by the new media environment for public relations practitioners?
A. Practitioners must stay abreast of technological developments in new media. B. Practitioners must give up their code of ethics to be effective. C. Practitioners must respond to the public demand for transparency. D. Practitioners must use corporate blogs to reach their publics. E. Practitioners must represent organizations in the new social media environment. B and
According to an InformationWeek survey of business technology experts, wikis are the most useful Web 2.0 tools in Enterprise 2.0
Indicate whether the statement is true or false
A ____ is a textual description of a data flow's content and internal structure
a. data store rule b. data flow definition c. data flow rule d. process definition
Marks Corporation has two operating departments, Drilling and Grinding, and an office. The three categories of office expenses are allocated to the two departments using different allocation bases. The following information is available for the current period: Office ExpensesTotal Allocation BasisSalaries$30,000 Number of employeesDepreciation 20,000 Cost of goods soldAdvertising 40,000 Net sales ItemDrilling Grinding TotalNumber of employees 1,000 1,500 2,500 Net sales$325,000 $475,000 $800,000 Cost of goods sold$75,000 $125,000 $200,000 The amount of depreciation that should be allocated to Drilling for the current period is:
A. $7,500. B. $25,000. C. $40,000. D. $20,000. E. $12,500.