title: Limitations with database computed column
body: <p>We have add a computed column in database. The value of this computed column is derived using two other columns. </p>
  
  <p>For example </p>
  
  <pre><code>COMPUTED_COLUMN = COLUMN_1 * COLUMN_2 
  </code></pre>
  
  <p>But now we noticed that <code>COLUMN_1</code>'s value is incorrect for some existing rows due to which computed column also have incorrect value. Unfortunately we can not update the value of <code>column_1</code>. </p>
  
  <p>Now we need to correct the computed column value for existing rows. I search it and found that computed column never updated. Is there some way to fix exiting rows value.. We can not change any existing column value. </p>
  
  <p>Thanks in advance for help.</p>