title: Joining on variables with two different formats
body: <p>I have a problem where I have a year of birth attribute in table X (format: yyyy)  as well as a date of birth attribute in table Y (different format: dd-mm-yyyy).</p>
  
  <p>They are both varchar() type attributes. I want to join these tables on these attributes. For example, I want to select the names of all the people born in the same year. How can I do this?</p>