Data | MCQs

Explanation

A foreign key is used to link two tables and can contain duplicate values.

In contrast, primary, candidate, and even secondary keys are typically unique.

Explanation

A primary key must be unique for each record and never change.

Zip code is not unique (many people can share the same zip code), so it's not suitable as a primary key.

Explanation

In an Entity-Relationship (E-R) diagram, a rectangle represents an Entity.

Attributes are shown as ellipses.

Relationships are shown as diamonds.

Explanation

DFD stands for Data Flow Diagram.

It is used to represent the flow of data in a system.

It shows how data moves between processes, data stores, and external entities.

Explanation

Data refers to raw facts and figures that have not yet been processed.

Once processed, data becomes information.

Explanation

An address is an identifiable location in computer memory where data is stored.

Each memory cell has a unique address used to access or modify data.

Explanation

Diarization in file movement refers to entering a reminder or note in an official diary or register for future action or follow-up.

It helps in tracking deadlines and ensures that important documents are not overlooked.

Explanation

The source and method of data collection significantly impact the accuracy of the data.

Different sources might have varying levels of reliability and accuracy.

The method used to collect data, whether through surveys, interviews, experiments,

Or other means can also introduce biases or errors.

For example, a survey with leading questions might yield biased results. 

Explanation

Explanation

Distributed data entry refers to the process where data is entered by multiple individuals or from multiple locations,

Eather than being done at a single central location

This approach can improve efficiency and speed in large-scale operations.