The defer and panic statements

The defer statement defers the execution of the function until the surrounding function returns. The panic function stops the current flow and control. Deferred functions are executed normally after the panic call. In the following code example, the defer call gets executed even when the panic call is invoked:

  defer database.Close()
  return customer
}
// GetCustomers method returns Customer Array
func GetCustomers() []Customer {
  var database *sql.DB
  database = GetConnection()
  var error error
  var rows *sql.Rows
  rows, error = database.Query("SELECT * FROM Customer ORDER BY Customerid DESC")
  if error != nil {
  panic(error.Error())
  }
  var customer Customer
  customer = Customer{}
  var customers []Customer
  customers= []Customer{}
  for rows.Next() {
  var customerId int
  var customerName string
  var ssn string
  error = rows.Scan(&customerId, &customerName, &ssn)
  if error != nil {
  panic(error.Error())
  }
  customer.CustomerId = customerId
  customer.CustomerName = customerName
  customer.SSN = ssn
  customers = append(customers, customer)
  }
  defer database.Close()
  return customers
}

Let's take a look at the InsertCustomer, UpdateCustomer, and DeleteCustomer methods in the following sections.