title: ALTER table in vertica
body: <p>I have table in Vertica which has time_stamp:int with value Unix timestamp, I want to alter this data type from  int to <code>TIMESTAMPTZ</code>;</p>
  
  <p>I tried </p>
  
  <pre><code>ALTER TABLE exploded_names ALTER COLUMN time_stamp SET DATA TYPE TIMESTAMPTZ;
  </code></pre>
  
  <p>But got following error </p>
  
  <pre>ROLLBACK 2353:  Cannot alter type of column "time_stamp" since it is referenced in the segmentation expression of projection "exploded_names_b0"</pre>
  
  <p>then I tried to drop that projection :</p>
  
  <pre><code>drop projection exploded_names_b0 CASCADE;
  </code></pre>
  
  <pre>ROLLBACK 4122:  No up-to-date super projection left on the anchor table of projection exploded_names_b0
  HINT:  Use DROP TABLE ... CASCADE to drop the anchor table and its last projection, or create a replacement super projection instead</pre>
  
  <p>I don't want to drop the table.</p>