Salesforce Recursive Triggers Fully Explained/Salesforce Scenario based discussion

Recursive Triggers:

 In general Recursion is executing the same task repeatedly. The Recursive trigger occurs when same trigger called it self multiple times which results in infinite loop. Which would throw an error without commiting the changes to database.

Scenario:

Apex Trigger : Below trigger invokes when new account record created into the database . The RecursionExample trigger try to insert new record with the Account Name 'TestAccount' .

trigger RecursionExample on Account (After Insert) {

    if(Trigger.isAfter&&Trigger.isInsert){
        Account acc = new Account(Name = 'TestAccount');
        Insert acc;
    }

}

Assume if TestAccount inserted into the system ,This will again invoke same trigger 'RecursionExample '  ,Since it would be After insert operation .This will again create another account record with the Account Name 'TestAccount'  and This will again invoke same trigger  it will continue infinite times which leads to below shown error .

Solution :  This Error can be avoided by setting the 'Boolean Static Variable' in the handler class.

Modified Trigger :

trigger RecursionExample on Account (After Insert) {

    if(Trigger.isAfter&&Trigger.isInsert){
        if(RecursionExampleHandler.isFirstTime){
            RecursionExampleHandler.isFirstTime=false;
            Account acc = new Account(Name = 'TestAccount');
            Insert acc;
        }
    }
}

Handler :

public class RecursionExampleHandler {
public static Boolean isFirstTime=True;
}

When Trigger runs for first time ,Handler class will be invoked from the trigger and it will setup 'isFirstTime' Static variable to True .During First trigger Run 'isFirstTime' Static variable will be changed to 'False' along with the Account creation with account name 'TestAccount' .When trigger tries to Run for second time ,Trigger will not get run since  'isFirstTime' has been set to 'False' and stops the transaction right there.

We hope your clear with the process now .

If you still require further clarifications,Please let us know in the comments .

Happy Learning☺☺☺