Salesforce Apex Triggers

It explains about

• What is trigger?

• Trigger Syntax

• How can you create or define a trigger?

• Trigger Events

It explains about the following things:

• Types of triggers?

• Trigger Context Variables

• An Example for Before Trigger and After Trigger

It explains about following scenario and achieve the same with trigger.

1. Create an opportunity when Account “Rating” changed to “Hot”

2. Prevent Account deletion when there is a primary contact under Account

It explains about how to test an apex trigger along with how to handle test class errors when we have addError() method in an apex trigger.

It explains about

how to writer Single Trigger and Bulk Trigger.

What happens if you write Single Trigger

Why do we need to write bulk trigger with simple example.

It explains about

How to do Custom roll-up using trigger with simple example?

Eg: Calculate and Display total number of contacts on Account

Advantage of count() method in aggregate Result.

It explains about a simple use case  and code the same.

Use Case:Prevent user to add more than 5 Opportunity Products under an opportunity

It explains about the trigger context variable "operationType" and the usage with Switch statement.

It explains about

How to do callout from an apex trigger?

What we have to consider to perform Callout from future method?

It explains about how to publish and subscribe platform events through apex triggers.

It explains about

How to handle recursion in apex trigger.

This explains how to calculate No of Files on an Account when the files are inserted or deleted.

It provides few mock interview questions and answers