← VCE Spreadsheets, SQL & Visualisation

Validation messages and error alerts

A message that pops up when someone enters data that breaks a validation rule. It can Stop the entry, Warn about it, or give Information, and a good message explains how to fix it.

Part of: VCE Applied Computing - U1O1 - Data analysis — Module 32, 7-8 Digital Technologies: Acquiring, storing and validating data — Module 15, ACARA Digital Technologies Years 7–8 — Acquiring and Storing Data — Module 71, ACARA Digital Technologies Years 9–10 — Acquiring and Validating Data — Module 70

Understanding Validation messages and error alerts in VCE Spreadsheets, SQL & Visualisation

What it does: An input message appears when the cell is selected and tells the user what to enter, so mistakes are less likely. A good error alert says what is allowed so the user can correct the entry, instead of just saying 'Wrong'. A Stop alert will not let a bad entry stay in the cell. You must enter a valid value or cancel. A Warning asks 'Do you want to continue?' so the user can keep the entry. Stop never allows it. A better message would be 'Enter a score between 0 and 100.' because it explains how to fix the entry.

Common mistakes: An Information alert lets the bad entry through. The goal is to block bad ages, so the alert style should be Stop. The error message says 0 to 10, but the rule allows 0 to 100. The message must match the rule: 'Error message: Enter 0 to 100'.

Class: _____________________  ·  Name: _____________________  ·  Date: _________

Free printable worksheet with full answer key — or add this module to a class and your students practise it interactively.

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This module's key terms are also in a printable crossword (Modules 21–34) and word search (Modules 4–34).

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Learning
Duo
Which message appears BEFORE you type, to tell you what to enter in a cell?
Input messageError alert
Matches
Error message: Bad!
↓
The message is not helpful. It does not say what is wrong or what the user should type instead.
Applying
Meanings
Term
Error alert
Meaning
A message that pops up when someone enters data that breaks a validation rule. It can Stop the entry, Warn about it, or give Information, and a good message explains how to fix it.
Practice
Allow: Whole number
Testing
Gaps
Error alert style:
Check Answer
Spots
3Goal: bad ages must be blocked
4Alert style: Information

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Quick Questions

1. Which message appears BEFORE you type, to tell you what to enter in a cell?
A. Input message ✓
B. Error alert
An input message shows up when you click the cell and guides you. An error alert only appears after a bad entry.
2. Which message appears AFTER you type data that breaks the validation rule?
A. Input message
B. Error alert ✓
The error alert pops up when the entry breaks the rule. The input message appears earlier, as a guide.
3. A Stop alert is set on a cell that only accepts ages from 11 to 14. You type 30. What happens?
A. The entry is blocked and you must fix it ✓
B. The 30 is accepted with a quick note
A Stop alert will not let a bad entry stay in the cell. You must enter a valid value or cancel.
4. Which alert type lets the user choose to keep a bad entry by clicking Yes?
A. Warning ✓
B. Stop
A Warning asks 'Do you want to continue?' so the user can keep the entry. Stop never allows it.
5. Which alert type just tells the user about the problem and still lets them click OK to keep the entry?
A. Stop
B. Information ✓
An Information alert gives a message only. The entry can stay if the user clicks OK.

Match the Pairs

Style: Stop → Blocks the bad entry completely. The user must fix it or cancel before moving on.
Style: Warning → Tells the user the entry looks wrong but lets them choose to keep it anyway.
An input message guides the user BEFORE they type, so they know what is allowed → Input message: Enter an age from 11 to 14
A helpful error message explains what went wrong and how to fix it → Error message: Pick a year level from 7 to 8
Error message: Bad! → The message is not helpful. It does not say what is wrong or what the user should type instead.
Style: Information (to block negative ages) → Information alerts only tell the user something and still allow the bad data. Stop should be used to block it.

Key Term

Error alert
A message that pops up when someone enters data that breaks a validation rule. It can Stop the entry, Warn about it, or give Information, and a good message explains how to fix it.

Fill in the Blanks

1. Rule: Whole number between 1 and 100 Error alert style: Stop Message: Enter a whole number from 1 to 100.
Hint: Type the alert style that completely blocks a bad entry.
2. Rule: Whole number between 1 and 100 Error alert style: Warning Message: Age should be 1 to 100. Keep it?
Hint: Type the alert style that warns the user but lets them choose to keep the entry.
3. Rule: Whole number between 1 and 100 Error alert style: Information Message: Only 1 to 100 is expected.
Hint: Type the alert style that just tells the user and lets the entry go through.
4. Input message: Type a mark from 0 to 100 Shows when the cell is selected
Hint: Type the kind of message that guides the user before they type anything.
5. Rule: List of Yes,No Error alert style: Stop Error alert message: Choose Yes or No.
Hint: Type the word for the text that explains to the user how to fix their mistake.

Spot the Error

Question 1
A Cell: B2
B Allow: Whole number 11 to 15
C Goal: bad ages must be blocked
D Alert style: Information
E Error message: Use 11 to 15
Line D — An Information alert lets the bad entry through. The goal is to block bad ages, so the alert style should be Stop.
Question 2
A Allow: Decimal 0 to 100
B Input message: Enter a mark
C Error message: Enter 0 to 10
D Alert style: Stop
Line C — The error message says 0 to 10, but the rule allows 0 to 100. The message must match the rule: 'Error message: Enter 0 to 100'.
Question 3
A Allow: List (Red,Blue,Green)
B Goal: warn but allow others
C Alert style: Stop
D Error message: Not on the list
Line C — The goal is to warn the user but still allow other entries. A Stop alert refuses them, so the style should be Warning.
Question 4
A Cell: C2
B Input message: Age is invalid!
C Allow: Whole number 11 to 15
D Error message: Use 11 to 15
Line B — An input message appears before the user types and should guide them. Saying the age is invalid sounds like an error. It should say something helpful like 'Type your age'.
Question 5
A Allow: Whole number 1 to 30
B Alert style: Stop
C Error message: Wrong!
D Input message: Enter 1 to 30
Line C — A good error message explains how to fix the problem. 'Wrong!' does not say what is allowed. It should be something like 'Pick 1 to 30'.

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