title: mysql UPDATE statement - overhead for same values?
body: <p>i have a large MYSQL database with hundreds of thousands of records. i want to update a field in a large number of them, but I am unaware if that field has been updated yet or not.</p>
  
  <p>if i call an update statement that sets authortype=10 and authortype is already 10 will this be faster than doing a separate query to only select those that aren't authortype=10 and then update them?</p>
  
  <p>in other words, if I set a value equal to what it is already, is that any faster than if I am updating a value to something new? again this is with tons and tons of records and I want to be efficient.</p>
  
  <p>thanks in advance</p>