LinkedIn Learning: Learning Data Analytics: 1 Foundations

Which items are examples of data cleaning? A. removing unnecessary columns B. changing the case of data (upper, lower, etc.) C. connecting to the data in a database D. removing unnecessary spaces from data

A, B, D—Removing columns, spaces, and changing case of data are all examples of data cleaning

Maintaining your original data set provides you with which option(s)? A. the benefit of not starting entirely back over after a mistake B. an audit trail C. a better understanding of your data D. none of these answers

A, B—Keeping a copy of the original data provides you the ability to just quickly start back over after a mistake. It will also give you the ability to return to the original data for auditing the work

When you are learning a new database, when should you look at a sample of the data?

After you look at the table names

You want to join records in tables that match with fields in other tables. To do this, which join will you use?

An inner join

Changes we make to our data in Power Query are recorded in _____.

Applied Steps—when making changes to the data in Power Query, it automatically tracks each step in the Applied steps.

What is not an example of a logical function?

Average is not considered a logical function, but an aggregate function

Which items are best practices for being effective in a meeting? A. Dive right into the data and information when it's your turn. B. Ask to be on the agenda and state how much time you need. C. Provide a list of key definitions and consider a slide deck.

B, C—As a data analyst, it is important that you have time to cover the information you need answers for your questions. Providing a key list of definitions up front is important to reduce time spent answering questions that you can answer with a simple document. Including a slide deck will help you stay focused and on point.

Merge Columns replaces what function in Excel?

Concat() and Concatenate() both combine values in Excel, and the outcome of Merge Columns is the same as both of these commands in Excel.

You should _____ the headers on a new sheet tab to provide valuable information with your data.

Copy and transpose—Transpose allows you to flip data from horizontal to vertical, which can be helpful when documenting information about fields and while providing data sets to others.

When data analysts consider all the data from any object, this is an example of them turning on their _____.

Data lens is something that a data analyst will improve over time. The more exposure to data you have, the more likely you are to think of data points when they are not exactly in front of you on a table or spreadsheet.

Which role needs the most technical and working experience?

Data scientist- typically have lots of real-world working experience. They are fluent in coding, math, and statistics, as well as all other required data roles, like data engineering, data cleaning, and reporting outcomes.

Reviewing table design is important for a data analyst. What is something you will discover in the design of tables?

Data types

What does a cross join or no join accomplish?

It associates every record to every record in both tables. When multiple tables are brought into a query, they must have a common field that links them together through a join. When this join line is missing, it will tie every record from one table to every record in another table

In Power Query, merge queries allow us to _____.

Join data together—merge queries are the database equivalent to writing a select query

Which option is not a reusable data set?

Order transactions—will change and be an overall part of the data we report and visualize. However, it is not what we consider reusable, like a date table or postal code data

You need a report for every day that occurred in a period of time. To determine if you had transactions on those days, which join would you use between your transactions table and date table?

Outer join—in order to pull every date from a range of dates you will tie your transactions table to a date table through an outer join.

Data governance involves _____.

People, technology, and processes—the best data governance will include not only people, but technology and processes to ensure that data is the highest quality, secured and meeting requirements.

One of the key ways to validate your queries is by knowing how many _____ you have in each data set.

Records—It is beyond important to know how many records are in the tables you are working with. This is one of the simplest ways to validate your joins.

In data, numbers are _____ aligned by default.

Right—Numbers are typically best read when they are right aligned by their last value. In data, it's also an indicator that the program sees values as numbers because it will default to right aligned.

Which choice is not a valid data type?

Start date is a field name and is likely a date and time data type

Knowing the statistical significance of any data point or set is an example of the _____ truth.

Stats

Which truth is a measure of an organization's production?

The business truth

There are many reasons to change case of any data. Using Proper() changes case to proper in Excel. What is the equivalent command in Power Query?

Transform > Capitalize each word is the same outcome as using the Proper() function in Excel

_____ code is written by recording macros in Microsoft Office.

VBA (Visual Basic for Applications)—code language that runs Microsoft Office products. When you create a macro, it is coding in the VBA.

A file that is not connected to a live data set, and that you receive through either email or an export, is an example of a(n) _____.

Flat file—data sets that are not directly connected to the data source. They are typically are exports to .csv or Excel files that you run yourself or have been emailed to you.

What command do you use to create aggregated data sets in Power Query?

Group By—will allow you to group data and add aggregate functions like SUM, COUNT and AVERAGE

What is a form of data cleaning and transformation?

Deleting columns or adding calculations to an Excel spreadsheet

It's not always obvious when looking at large data sets that data is duplicated. Which command in Excel lets you easily highlight duplicate values?

Excel Conditional Formatting has a highlight option that will immediately apply formatting that shows duplicated data

When starting a new data project, what is one of the best sources to help you begin?

Existing reports- learning about what is currently being reported will help you understand the organization. Using existing reports, you can often reverse engineer the data to begin your own projects