title: Performance difference between UUID, CHAR, and VARCHAR in PostgreSql table?
body: <p>I'm storing UUID v4 values in a PostgreSQL v9.4 table, under column "id".</p>
  
  <p>When I create the table, is there any difference in following write or read performance whether I define the "id" column as <a href="http://www.postgresql.org/docs/9.4/static/datatype-character.html" rel="noreferrer">VARCHAR(36), CHAR(36)</a>, or <a href="http://www.postgresql.org/docs/9.4/static/datatype-uuid.html" rel="noreferrer">UUID</a> data type?</p>
  
  <p>Thanks!</p>