title: Liquibase - insert new row based on data from existing column
body: <p>If I have a DB table like:</p>
  
  <p>Column 1 Column 2<br>
  Data1, Data2a<br>
  Data2, Data2b<br>
  Data3, Data2a  </p>
  
  <p>Is it possible to create a liquibase changeset script to get all the unique values from Column 2, and use that data to insert new rows?</p>
  
  <p>Such that my final table could look like (Actual values of Column 1 inserted will be manually defined by myself)</p>
  
  <p>Column 1 Column 2<br>
  Data1, Data2a<br>
  Data2, Data2b<br>
  Data3, Data2a<br>
  Data4, Data2a //Got this value from initial table<br>
  Data5, Data2b //Got this value from initial table  </p>