Free Salesforce Platform Developer 1 Practice Exam (With Answers)

If we wish for a method or a variable to be able accept any type of Salesforce Object, we use the SObject type class. All Salesforce Objects extend the generic SObject class and so, when a method must accept different types of objects, we must define our datatype to be the generic SObject type instead.

While it is true that we could also use 2 – Object data type – since everything in Apex extends this type, it would allow our method to take in unnecessary data types, such as Boolean or String.

The Wire service is designed to provision a component with an immutable stream of data to a component that is ever updating. Because of this, the values returned by the Apex methods must be cached and so we must always annotate a method intended to be used by the Wire service with @AuraEnabled (cacheable = true).

References:

• Understand the Wire Service
• Wire Apex Methods to Lightning Web Components

The StandardSetController is designed to work with sets of records, and so provides built in methods to enable a large set of records to be displayed on a Visualforce page, with methods to assist in pagination of the record list.

References:

• Pagination with a List Controller
• Visualforce StandardSetController methods

The SOQL engine within Apex is incredibly flexible in how we can call it, and how it returns data for us to consume with the code. The most common return type is a List<SObjects>, this will be when a simple query is run. The SObject return type can be used when a query is known to return a single record only, for example when using a LIMIT 1 or querying for a specific ID. The integer return type is used when we use the COUNT query function.

References:

• SOQL and SOSL Queries

SOQL for loops differ from a traditional for loop, or a List/Set for loop in that they can utilise more efficient chunking of SObjects behind the scenes, resulting in a reduced heap usage and a lower chance of hitting governor limits for large queries. This type of loop should be the tool of choice when iterating over query results as it can mitigate the chance of hitting errors as a dataset scales.

References:

• SOQL For Loops

The multi-tenant architecture within Salesforce presents developers with several considerations that must be taken when they are writing code for the platform.

The design of the multi-tenant system prevents any data from being accessed outside it’s intended org, which means additional security considerations (outside the usual ones) aren’t required, simply because of the multi-tenant nature.

The platform resources are, however, shared and all orgs within instances are using the same CPUs and memory for all of their Apex operations and it is here where the considerations must be made. These considerations are to ensure that Apex code is performant as any code deemed to be using excessive resources (as defined by the governor limits) will be terminated to prevent it from monopolising resources and causing detrimental effects on other tenants.

References:

• Salesforce's Multi Tenant Architecture

All data stored within a number field (or number returning formula) is represented as a Double when accessed within Apex.

Reference:

• API Data Types and Salesforce Field Types