title: How can I alter a UDT in HSQLDB?
body: <p>In HSLQDB v 2.3.1 there is a <code>create type</code> clause for defining UDTs. But there appears to be no <code>alter type</code> clause, as far as the docs are concerned (and the db returns a <code>unexpected token</code> error if I try this).</p>
  
  <p>Is it possible to amend/drop a UDT in HSQLDB? What would be the best practice, if for example I originally created</p>
  
  <pre><code>create type CURRENCY_ID as char(3)
  </code></pre>
  
  <p>because I decide I'm going to use ISO codes. But then I actually decide that I'm going to store the codes as integers instead. What is the best way to modify the schema in my db? (this is a synthetic example, obviously I wouldn't use integers in this case).</p>
  
  <p>I guess I might do</p>
  
  <pre><code>alter table inventory alter column ccy set data type int
  drop type CURRENCY_ID
  create type CURRENCY_ID as int
  alter table inventory alter column ccy set data type CURRENCY_ID
  </code></pre>
  
  <p>but is there a better way to do this?</p>