title: Change datatype of column to uniqueidentifier from bigint
body: <p>I want to change the datatype of a column in a table in sql server. I used the following statement:</p>
  
  <pre><code>ALTER TABLE dbo.tbltest  
  ALTER COLUMN ID uniqueidentifier
  </code></pre>
  
  <p>But it throws the error</p>
  
  <blockquote>
    <p>Operand type clash: bigint is incompatible with uniqueidentifier</p>
  </blockquote>