title: how to convert base64 string to bytea in postgresql8.2
body: <p>I need to convert base64 string to bytea type. But when I Executed SQL statements by the pgAdminIII：</p>
  
  <p><code>select decode("ygAAA", 'base64');</code></p>
  
  <p>I got the following error message:</p>
  
  <pre><code>ERROR:  syntax error at or near ")"
  LINE 1: select decode('ygAAA', 'base64');
                                                                ^
  ********** 错误 **********
  
  ERROR: syntax error at or near ")"
  SQL 状态: 42601
  字符:59
  </code></pre>
  
  <p>My postgresql's version is 8.2.15. And I could use encode function.
  I googled it, but didn't find the solution. Can somebody help me? TKS!</p>