title: Liquibase: How to drop unique constraint with no constraint name?
body: <p>This is what my column looks like  </p>
  
  <pre><code>        &lt;column name="name" type="VARCHAR(255)"&gt;
              &lt;constraints nullable="false" unique="true"/&gt;
          &lt;/column&gt;
  </code></pre>
  
  <p>I want to remove <code>unique=true</code> constraint. </p>
  
  <p>I looked at what <a href="http://www.liquibase.org/documentation/changes/drop_unique_constraint.html">liquibase</a> has to offer and it has  </p>
  
  <pre><code>&lt;changeSet author="liquibase-docs" id="dropUniqueConstraint-example"&gt;
      &lt;dropUniqueConstraint catalogName="cat"
              constraintName="const_name"
              schemaName="public"
              tableName="person"
              uniqueColumns="A String"/&gt;
  &lt;/changeSet&gt;
  </code></pre>
  
  <p>Now since <code>constraintName</code> is required and I do not have it, what are my options?  </p>
  
  <p>How can I drop <code>unique=true</code> using liquibase?</p>