Salesforce DEX-450 Online Practice Questions and Exam Preparation

Salesforce DEX-450 Online Questions & Answers

• Question 241:

  How would a developer change the field type of a custom field on the Account object from string to an integer?

  A. Make the changes in the developer console, and then the change will automatically be reflected in the Apex code.
  B. Mate the change in the declarative UI, then update the field type to an integer field in the Apex code.
  C. Make the change in the declarative UI, an then the change will automatically be reflected in the Apex code.
  D. Remove all references in the code, make the change in the declarative UI, and restore the references with the new type.
  D. Remove all references in the code, make the change in the declarative UI, and restore the references with the new type.

• Question 242:

  A company has a custom object named Warehouse. Each Warehouse record has a distinct record owner, and is related to a parent Account in Salesforce.Which kind of relationship would a developer use to relate the Account to the Warehouse?

  A. One -to -Many
  B. Lookup
  C. Master -Detail
  D. Parent -Child
  B. Lookup

• Question 243:

  A developer needs to have records with specific field values in order to test a new Apex class. What should the developer do to ensure the data is available to the test?

  A. Use Test.loadData() and reference a CSV file.
  B. Use SOQL to query the org for the required data.
  C. Use Test.loadData() and reference a static resource.
  D. Use Anonymous Apex to create the required data.
  C. Use Test.loadData() and reference a static resource.

• Question 244:

  A developer wants to handle the click event for a lightning:button component. The on click attribute for the component references a JavaScript function in which resource in the component bundle?

  A. Helper.js
  B. Handler.js
  C. Controller.js
  D. Renderer.js
  C. Controller.js

• Question 245:

  A developer must create a DrawList class that provides capabilities defined in the Sortable and Drawable interfaces. public interface Sortable { void sort(); } public interface Drawable { void draw(); } Which is the correct implementation?

  A. Public class DrawList implements Sortable, Implements Drawable { public void sort() { /*implementation*/} public void draw() { /*implementation*/} ]
  B. Public class DrawList extends Sortable, Drawable { public void sort() { /*implementation*/} public void draw() { /*implementation*/} }
  C. Public class DrawList implements Sortable, Drawable { public void sort() { /*implementation*/} public void draw() { /*implementation*/} }
  D. Public class DrawList extends Sortable, extends Sortable, extends Drawable { public void sort() { /*implementation*/ } public void draw() { /* implementation */}
  C. Public class DrawList implements Sortable, Drawable { public void sort() { /*implementation*/} public void draw() { /*implementation*/} }

• Question 246:

  A developer working on a time management application wants to make total hours for each timecard available to applications users. A timecard entry has a Master-Detail relationship to a timecard. Which approach should the developer use to accomplish this declaratively?

  A. A visualforce page that calculates the total number of hours for a timecard and displays it on the page.
  B. An Apex trigger that uses an Aggregate Query to calculate the hours for a given timecard and stores it in a custom field.
  C. A Roll-up Summary field on the Timecard Object that calculates the total hours from timecard entries for that timecard.
  D. A Process Builder process that updates a field on the timecard entry is created.
  C. A Roll-up Summary field on the Timecard Object that calculates the total hours from timecard entries for that timecard.

• Question 247:

  How should a developer prevent a recursive trigger?

  A. Use a "one trigger per object" pattern.
  B. Use a static Boolean variable.
  C. Use a trigger handler.
  D. Use a private Boolean variable.
  D. Use a private Boolean variable.

• Question 248:

  A developer has the following code:

  try {List nameList;Account a;String s = a.Name;nameList.add(s);} catch (ListException le ) {System.debug(' List Exception ');} catch (NullPointerException npe) {System.debug('

  NullPointer Exception ');} catch (Exception e) {System.debug(' Generic Exception ');}

  What message will be logged?

  A. List Exception
  B. NullPointer Exception
  C. Generic Exception
  D. No message is logged
  B. NullPointer Exception

• Question 249:

  How can a developer warn users of SOQL governor limit violations in a trigger?

  A. Use ApexMessage.Message() to display an error message after the number of SOQL queries exceeds the limit.
  B. Use PageReference.setRedirect() to redirect the user to a custom Visualforce page before the number of SOQL queries exceeds the limit.
  C. Use Messaging.SendEmail() to continue the transaction and send an alert to the user after the number of SOQL queries exceeds the limit.
  D. Use Limits.getQueries() and display an error message before the number of SOQL queries exceeds the limit.
  D. Use Limits.getQueries() and display an error message before the number of SOQL queries exceeds the limit.

• Question 250:

  What is a capability of the tag that is used for loading external Javascript libraries in Lightning Component? (Choose three.)

  A. Loading files from Documents.
  B. One-time loading for duplicate scripts.
  C. Specifying loading order.
  D. Loading scripts in parallel.
  E. Loading externally hosted scripts.
  B. One-time loading for duplicate scripts.
  C. Specifying loading order.
  D. Loading scripts in parallel.