title: SQL: set value with condition
body: <p>I have some Problem, there are two Tables, they communicate with the value ID.
  Now I will set the value from Column <strong>a</strong> in Table <strong>A</strong> with the value 'Nein', but only if the value of the column <strong>b</strong> in Table <strong>B</strong> is '0' and 
  if a.id = b.id.</p>
  
  <p>How can I do that?
  Thanks</p>