Salesforce Salesforce Certifications DEX-450 Questions & Answers

• Question 221:

  Which action can a developer perform in a before update trigger? (Choose 2)

  A. Display a custom error message in the application interface.

  B. Change field values using the Trigger.new context variable.

  C. Delete the original object using a delete DML operation.

  D. Update the original object using an update DML operation.

  Correct Answer: AB

• Question 222:

  A developer wants to handle the click event for a lightning:button componentthe onclick attribute for the component references a javascript function in which resource in the component bundle?

  A. Helper.js

  B. Handler.js

  C. Renderer.js

  D. Controller.js

  Correct Answer: D

• Question 223:

  Which declarative method helps ensure quality data? (Choose 3)

  A. Validation Rules

  B. Workflow alerts

  C. Exception Handling

  D. Lookup Filters

  E. Page Layouts

  Correct Answer: ADE

• Question 224:

  Which two queries can a developer use in a visualforce controller to protect against SOQL injection Vulnerabilities? Choose 2 answers

  A. String qryName = '%' + String.enforceSecurityChecks(name)+ '%'; String qryString = 'SELECT Id FROM Contact WHERE Name LIKE :qryNAme'; List queryResults = Database.query(qryString);

  B. String qryName = '%' + name '%'; String qryString = 'SELECT Id FROM Contact WHERE Name LIKE :qryNAme'; List queryResults = Database.query(qryString);

  C. String qryName = '%' + String.escpaeSingleQuotes(name)+ '%'; String qryString = 'SELECT Id FROM Contact WHERE Name LIKE :qryNAme'; List queryResults = Database.query(qryString);

  D. String qryString = 'SELECT Id FROM Contact WHERE Name LIKE :qryNAme'; List queryResults = Database.query(qryString);

  Correct Answer: AD

• Question 225:

  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.

  Correct Answer: D

• Question 226:

  Which collection type provides unique key/value pairings of data?

  A. Map

  B. List

  C. Array

  D. Set

  Correct Answer: A

• Question 227:

  What is a good practice for a developer to follow when writing a trigger? (Choose 2)

  A. Using @future methods to perform DML operations.

  B. Using the Map data structure to hold query results by ID.

  C. Using the Set data structure to ensure distinct records.

  D. Using synchronous callouts to call external systems.

  Correct Answer: BC

• Question 228:

  What are two considerations for deciding to use a roll-up summary field? Choose 2 answer's partner.

  A. Roll-up summary can be performed on formula fields, but if their formula contains an #Error result, it may affect the summary value.

  B. Roll-up summary fields do not cause validation rules on the parent object unless that object is edited separately.

  C. Roll-up cannot be performed on formula fields.

  D. Roll-up cannot be performed on formula fields that use cross-object references or on-the-fly calculations such as NOW().

  Correct Answer: AD

• Question 229:

  Which two ways can a developer instantiate a PageReference in Apex? Choose 2 answers A. By using an object standard set controller action

  B. By using ApexPages.currentPage()

  C. By using the PageReference.getURL() method

  D. By using an object standard controller action

  Correct Answer: AC

• Question 230:

  A developer needs to write a method that searches for a phone number that could be on multiple object types. Which method should the developer use to accomplish this task?

  A. SOQL Query that includes ALL ROWS

  B. SOQL query on each object

  C. SOSL Query that includes ALL ROWS

  D. SOSL query on each object

  Correct Answer: C