title: Converting varchar column to date column in Oracle
body: <p>I need to change column type from VARCHAR2 to DATE. The column is already storing dates in correct format. So I was trying to do something like this</p>
  
  <pre><code>alter INM_INCIDENT rename column INM_I_REACTION_TIME to INM_I_REACTION_TIME_OLD;
  alter table INM_INCIDENT add INM_I_REACTION_TIME date;
  update INM_INCIDENT set INM_I_REACTION_TIME = to_date(INM_I_REACTION_TIME_OLD);
  alter table INM_INCIDENT drop column INM_I_REACTION_TIME_OLD;
  </code></pre>
  
  <p>But I've got error on the line with update statement, so my question is, is there any nice solution for copying varchar to date like this?</p>