From trigger beforeInsert how to stop the insert in the database table [duplicate]

Question

Is there a possibilty in Salesforce from trigger beforeInsert how to stop the insert in the database table.

Answer 1

Using the SObject method addError on a record will prevent any DML operations (including inserts) from occurring on that record.

trigger preventContactInserts on Contact (before insert) {
  for (Contact c : Trigger.new) {
    if (c.FirstName=='Brian' && c.LastName=='Mansfield') {
      c.addError('You can't insert this record.');
    }
  }
}