Sort-Object for ordering in PowerShell - Practice Problems & Coding Challenges

Challenge - 5 Problems

💻 Command Output

intermediate

What is the output of this Sort-Object command?

Given this PowerShell command, what will be the output?

PowerShell

1..5 | Sort-Object -Descending

A Error: Parameter set cannot be resolved

B 1 2 3 4 5

C 5 4 3 2 1

D 5 3 1 2 4

💡 Hint

Think about what -Descending does to a list of numbers.

Sort-Object with -Descending sorts the numbers from highest to lowest, so 5 4 3 2 1.

💻 Command Output

intermediate

What does this Sort-Object command output?

What is the output of this command?

PowerShell

'apple','banana','cherry' | Sort-Object Length

A apple banana cherry

B banana cherry apple

C apple cherry banana

D cherry apple banana

💡 Hint

Sort by the length of each word from shortest to longest.

Sort-Object Length sorts strings by their length ascending: apple(5), banana(6), cherry(6). Since banana and cherry have same length, original order is preserved for them.

📝 Syntax

advanced

Which option correctly sorts objects by a property in descending order?

You have objects with a property 'Age'. Which command sorts them descending by Age?

PowerShell

$people = @(@{Name='Ann';Age=30}, @{Name='Bob';Age=25}, @{Name='Cara';Age=35})

A $people | Sort-Object -Property Age -Descending

B $people | Sort-Object Age Descending

C $people | Sort-Object -Age -Descending

D $people | Sort-Object -Property Age Desc

💡 Hint

Check the correct syntax for Sort-Object parameters.

Option A uses correct parameter names: -Property Age and -Descending switch. Others have syntax errors or invalid parameters.

🚀 Application

advanced

How to sort files by LastWriteTime descending?

You want to list files sorted by last modified date, newest first. Which command works?

PowerShell

Get-ChildItem | ???

A Sort-Object -Property LastWriteTime Desc

B Sort-Object LastWriteTime Descending

C Sort-Object -LastWriteTime -Descending

D Sort-Object -Property LastWriteTime -Descending

💡 Hint

Use the correct parameter names and switches for Sort-Object.

Only option D uses correct syntax with -Property and -Descending switch. A lacks '-' before Descending, making it invalid.

🧠 Conceptual

expert

What error does this Sort-Object command raise?

What error occurs when running this command?

PowerShell

1..5 | Sort-Object -Property NonExistentProperty

A No error, outputs original list

B PropertyNotFoundException

C SyntaxError

D NullReferenceException

💡 Hint

Think about what happens if you sort by a property that does not exist.

Sort-Object throws a PropertyNotFoundException when the property does not exist on the objects.

Practice

1. What does the PowerShell cmdlet Sort-Object do?

easy

A. It creates new objects from scratch.

B. It arranges objects in a specified order based on property values.

C. It deletes objects from a list.

D. It counts the number of objects in a list.

Solution

1. Step 1: Understand the purpose of Sort-Object

   Sort-Object is used to order or arrange objects based on their properties or values.

2. Step 2: Compare options with the cmdlet's function

   Only It arranges objects in a specified order based on property values. correctly describes arranging objects in order. Other options describe unrelated actions.

3. Final Answer:

   It arranges objects in a specified order based on property values. -> Option B

4. Quick Check:

   Sort-Object orders data = C [OK]

Hint: Sort-Object means arranging data in order [OK]

Common Mistakes:

• Confusing sorting with deleting or counting
• Thinking Sort-Object creates new objects
• Assuming it only works on numbers

2. Which of the following is the correct syntax to sort a list of numbers stored in $numbers in descending order?

easy

A. $numbers | Sort-Object Descending

B. $numbers | Sort-Object /Descending

C. $numbers | Sort-Object -descend

D. $numbers | Sort-Object -Descending

Solution

1. Step 1: Recall the correct parameter for descending order

   The correct parameter is -Descending with a dash and full word.

2. Step 2: Check each option's syntax

   $numbers | Sort-Object -Descending uses the correct dash and spelling. Options A, C, and D have syntax errors or wrong parameter format.

3. Final Answer:

   $numbers | Sort-Object -Descending -> Option D

4. Quick Check:

   Use dash and full '-Descending' [OK]

Hint: Use dash before parameters like -Descending [OK]

Common Mistakes:

• Omitting the dash before parameters
• Using incorrect parameter spelling
• Using slashes instead of dashes

3. What is the output of this PowerShell code?

$data = @( @{Name='John'; Age=30}, @{Name='Anna'; Age=25}, @{Name='Mike'; Age=35} )
$data | Sort-Object Age | ForEach-Object { $_.Name }

medium

A. Anna, John, Mike

B. John, Anna, Mike

C. Mike, John, Anna

D. Anna, Mike, John

Solution

1. Step 1: Understand sorting by Age property

   The code sorts the array of objects by the Age property in ascending order: 25, 30, 35.

2. Step 2: Map sorted objects to their Name property

   After sorting, the names in order are Anna (25), John (30), Mike (35).

3. Final Answer:

   Anna, John, Mike -> Option A

4. Quick Check:

   Sort by Age ascending = Anna, John, Mike [OK]

Hint: Sort-Object defaults to ascending order [OK]

Common Mistakes:

• Assuming Sort-Object sorts descending by default
• Mixing up property names
• Not accessing the Name property after sorting

4. You run this code but get an error:

$items = @(5, 3, 8, 1)
$items | Sort-Object -descendingg

What is the problem?

medium

A. You must use parentheses around the array.

B. Sort-Object cannot sort numbers.

C. The parameter '-descendingg' is misspelled.

D. The pipe operator '|' is not allowed here.

Solution

1. Step 1: Check the parameter spelling

   The parameter should be -Descending, but it is misspelled as -descendingg.

2. Step 2: Understand impact of misspelling

   PowerShell does not recognize the misspelled parameter, causing an error.

3. Final Answer:

   The parameter '-descendingg' is misspelled. -> Option C

4. Quick Check:

   Parameter spelling must be exact [OK]

Hint: Check parameter spelling carefully [OK]

Common Mistakes:

• Misspelling parameters
• Thinking Sort-Object can't sort numbers
• Misunderstanding pipe usage

5. You have this list of objects:

$people = @( @{Name='Sam'; Score=90}, @{Name='Liz'; Score=90}, @{Name='Tom'; Score=85} )

You want to sort by Score descending, but if scores are equal, sort by Name ascending. Which command achieves this?

hard

A. $people | Sort-Object -Property @{Expression='Score';Descending=$true}, @{Expression='Name';Descending=$false}

B. $people | Sort-Object Name, Score -Descending

C. $people | Sort-Object Score -Descending | Sort-Object Name

D. $people | Sort-Object -Property Score, Name -Descending

Solution

1. Step 1: Understand sorting by multiple properties with different orders

   You want Score sorted descending and Name sorted ascending when scores tie.

2. Step 2: Analyze each option's approach

   $people | Sort-Object -Property @{Expression='Score';Descending=$true}, @{Expression='Name';Descending=$false} uses script blocks to specify descending for Score and ascending for Name correctly. $people | Sort-Object -Property Score, Name -Descending applies descending to both, which is wrong. $people | Sort-Object Score -Descending | Sort-Object Name sorts twice, losing the first order. $people | Sort-Object Name, Score -Descending sorts Name first, which is incorrect order.

3. Final Answer:

   $people | Sort-Object -Property @{Expression='Score';Descending=$true}, @{Expression='Name';Descending=$false} -> Option A

4. Quick Check:

   Use script blocks for mixed ascending/descending [OK]

Hint: Use script blocks to mix ascending and descending [OK]

Common Mistakes:

• Applying -Descending to all properties at once
• Sorting twice losing original order
• Sorting properties in wrong priority order