title: SQL: Cancel 'where' on null parameter
body: <p>This may be obvious but I'm getting very confused.</p>
  
  <p>I have an SQL query with a where clause (where in with a list of parameters). If all of these parameters are null, I need the SQL to ignore the where clause and retrieve all the records. Is this easy to do in SQL? I know one way around it is to just remove the where clause using code if the parameters are null.</p>