title: Append to column-string without reading it from Database
body: <p>how is it possible to append to a column (type string) without reading the whole value from the database.</p>
  
  <p>Let's say the column, named "mycol" contains the string 'TESTtestTEST' and now I want to APPEND to this string the value 'abc', so 'TESTtestTESTabc' is stored in column mycol.</p>
  
  <p>How can I do this?</p>
  
  <p>Thank you very much for your help!</p>