title: combination of unique values a column in a table
body: <p>I need to find the all unique possible combination of values in a column in a table. For example, for column values 1,2,3,4,5. i want the result to be [1,2],[1,3],[1,4],[1,5],[2,1],[2,3] etc.</p>
  
  <p>Will appreciate any pointers to construct the query to find the combination of the values.</p>
  
  <p>thanks </p>