Hello,

           I am in scenerio in which whenever a new record is inserted by the user with the last name 'kumar' an email should be send to the email after fetching the email id from the email field present in the new record. This thing i am trying through trigger and that code is:

trigger updateDml2 on dml2__c (after insert, after Update) {
    String[] toAddresses;
    string message;
    for(dml2__c d2 : Trigger.new){
        if(d2.Last_Name__c == 'kumar'){
            
            String emailID = [select Email__c from dml2__c where Last_Name__c = 'kumar'].Email__c;
            Messaging.SingleEmailMessage mail1 = new Messaging.SingleEmailMessage();
            toAddresses = new String[] {emailID};
            mail1.setToAddresses(toAddresses);
            message = 'Email alert when the new record is populated with the last name kumar...!!!';
            mail1.setHtmlBody(message);
            Messaging.sendEmail(new Messaging.SingleEmailMessage[]{mail1});
        }
    }
}

 But the problem i am facing is:

             This code is running fine when the record is inserted by one user as it return by query only one email id, but it generates the error when the query return the multiple records.

For the mass email i tried this code but it show the following error. I think the query returning the records of Email__c should be placed into toAddresses but i unable to do this.

List<dml2__c> emailID = [select Email__c from dml2__c];
            Messaging.MassEmailMessage mail1 = new Messaging.MassEmailMessage();
            toAddresses = new String[] {emailID.Email__c};
            mail1.setToAddresses(toAddresses);
            message = 'Email alert when the new record is populated with the last name kumar...!!!';
            mail1.setHtmlBody(message);
            Messaging.sendEmail(new Messaging.MassEmailMessage[]{mail1});

I am unable to figure out the problem. Is there any way to solve this problem.

Thanks in advance.

Raju