Describe a dependency diagram and explain its purpose


Dependency diagrams are very helpful in getting a bird's eye view of all the relationships among a table's attributes, and their use makes it less likely that you will overlook an important dependency.
The following are features of a dependency diagram:
1 . The primary key attributes are bold, underlined, and shaded in a different color.
2 . The arrows above the attributes indicate all desirable dependencies—that is, dependencies based on the primary key.
3 . The arrows below the dependency diagram indicate less desirable dependencies. Two types of such dependencies exist:
a . Partial dependencies. A dependency based on only a part of a composite primary key is a partial dependency.
b. Transitive dependencies. A transitive dependency is a dependency of one nonprime attribute on another nonprime attribute. The problem with transitive dependencies is that they still yield data anomalies.

Business

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Wireless technologies enable what some people call mobile commerce, or _____.

Fill in the blank(s) with the appropriate word(s).

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Better Deals Company has 6 units in inventory on December 31. The units were purchased in November for $155 each. The price lists from the suppliers indicate that the same items would now cost the company a total of $960. What would be the amount reported as ending Merchandise Inventory on the balance sheet?

A) $1,890 B) $315 C) $930 D) $960

Business

When the prospect said, "I know that your company usually ships in batches of 6 dozen cases, but I don't have room to store that much merchandise." The salesperson must first:

A. determine if the objection is major or minor. B. determine if the prospect is setting a condition. C. smoke out the hidden and hopeless objections. D. try to negotiate with the customer to make a sale. E. use a dodge to create interest in the prospect.

Business

Which of the following is true?

a. Employees receive stock rights as a form of compensation. b. Employees in general may not transfer or sell stock rights to others. c. Stock rights give shareholders the right to purchase shares of common stock at half-price. d. Stock rights usually do not trade in public markets. e. Firms grant stock rights to current shareholders.

Business