title: Mysql VARCHAR to CHAR conversion behavior question
body: <p>I'm looking at this Mysql question <a href="http://dba.fyicenter.com/Interview-Questions/MySQL/When_you_create_a_table_and_then_run_SHOW_CREAT.html" rel="nofollow">link</a>:</p>
  
  <p>And I can't repeat the behavior described in the answer to that question.</p>
  
  <p>I tried creating tables with CHAR and VARCHAR column of various lengths and it doesn't matter what length - SHOW CREATE TABLE always return the data type that I've originally defined.</p>
  
  <p>So - no CHAR->VARCHAR switching is going on.</p>
  
  <p>Is answer to the question below only partially correct (I'm talking only about items 1 and 2)?</p>
  
  <hr>
  
  <p>Q:
  When you create a table, and then run SHOW CREATE TABLE on it, you occasionally get different results than what you typed in. What does MySQL modify in your newly created tables?</p>
  
  <p>A (supposedly):</p>
  
  <ol>
  <li><p>VARCHARs with length less than 4 become CHARs</p></li>
  <li><p>CHARs with length more than 3 become VARCHARs.</p></li>
  <li><p>NOT NULL gets added to the columns declared as PRIMARY KEYs</p></li>
  <li><p>Default values such as NULL are specified for each column</p></li>
  </ol>
  
  <hr>