Which of the following are reasons to create and maintain a data dictionary? (Choose two.)
Correct Answer: B,D
A data dictionary is a collection of metadata that describes the data elements in a database or dataset. It can help improve data acquisition by providing information about the data sources, formats, quality, and usage. It can also help remember specifics about data fields, such as their names, definitions, types, sizes, and relationships. Therefore, options B and D are correct. Option A is incorrect because it is not a reason to create and maintain a data dictionary, but a benefit of doing so. Option C is incorrect because specifying user groups for databases is not a function of a data dictionary, but a function of a database management system or a security policy. Option E is incorrect because confining breaches of PHI data is not a function of a data dictionary, but a function of a data protection or encryption system. Option F is incorrect because reducing processing power requirements is not a function of a data dictionary, but a function of a data compression or optimization system.
Question 177
The duration of a phone call in milliseconds is an example of:
Correct Answer: D
Explanation The correct answer is D. Continuous data. Continuous data is a type of quantitative data that can take any value within a range and can be measured with infinite precision. Continuous data can be expressed as fractions, decimals, or percentages. Examples of continuous data are height, weight, temperature, time, speed, etc12 The duration of a phone call in milliseconds is an example of continuous data, because it can take any value within a range (from zero to infinity) and can be measured with infinite precision (up to milliseconds or even smaller units). The duration of a phone call in milliseconds can also be expressed as fractions, decimals, or percentages of a larger unit (such as seconds, minutes, or hours). Ordinal data is not correct, because ordinal data is a type of qualitative or categorical data that can be ordered or ranked according to some criterion. Ordinal data can have a logical order, but the intervals between the values are not equal or meaningful. Examples of ordinal data are grades, ratings, ranks, etc12 Nominal data is not correct, because nominal data is a type of qualitative or categorical data that can be labeled or named without any order or ranking. Nominal data can have a finite number of categories or classes, but the categories have no intrinsic value or hierarchy. Examples of nominal data are gender, color, nationality, etc12 Boolean data is not correct, because boolean data is a type of binary data that can have only two possible values: true or false. Boolean data can be used to represent logical statements, conditions, or outcomes. Examples of boolean data are yes/no, on/off, 1/0, etc.
Question 178
What GAPP principle says that organizations should provide data subjects with the ability to review and update their personal information?
Correct Answer: C
Question 179
A customer list from a financial services company is shown below: A data analyst wants to create a likely-to-buy score on a scale from 0 to 100, based on an average of the three numerical variables: number of credit cards, age, and income. Which of the following should the analyst do to the variables to ensure they all have the same weight in the score calculation?
Correct Answer: D
Explanation Normalizing the variables means scaling them to a common range, such as 0 to 1 or -1 to 1, so that they have the same weight in the score calculation. Recoding the variables means changing their values or categories, which would alter their meaning and distribution. Calculating the percentiles of the variables means ranking them relative to each other, which would not account for their actual magnitudes. Calculating the standard deviations of the variables means measuring their variability, which would not make them comparable. References: CompTIA Data+ Certification Exam Objectives, page 10
Question 180
What SQL command is used to delete an entire table from a database?
