Duplicate account trigger

The following Trigger will fires when we try to create the account with same name i.e Preventing the users to create Duplicate Accounts.


Trigger duplicateAccTrigger on Account (Before Insert){
  switch on Trigger.operationType {
    when BEFORE_INSERT {
    duplicateAccHelper.checkDuplicateAcc(Trigger.new);
    }
  }
}

Public with sharing duplicateAccHelper {
  public static void checkDuplicateAcc(List<account> accLst){
  if(accLst != null || accLst.size() > 0){
  for(Account acc : accLst){
  List<Account> accCheck = [SELECT Id, name from account where name = acc.name AND rating= acc.rating];
  if(accCheck.size() > 0 ){
  acc.name.addError = 'Account is already been created';
  }
  }
  }
  }
}