title: SQL Server: Select only one row of rows that has the same ID on some coulmn
body: <p>I have a table that has 3 columns:
   - ID
   - FROM
   - TO
  And i have data like that</p>
  
  <pre><code>-----------------------
  ID   |   FROM   |   TO
  1    |   2      |   1
  2    |   5      |   1
  3    |   7      |   1
  4    |   2      |   1
  5    |   2      |   1
  6    |   9      |   1
  7    |   3      |   1
  8    |   4      |   1
  9    |   5      |   1
  </code></pre>
  
  <p>I would like to create a query that selects all rows where TO = 1 and i don't want to display rows that was previously retrieved, for example i have multiple rows where FROM = 2 and TO = 1, i just need to retrieve that row only once.</p>
  
  <p>My table doesn't really look like this but i am giving a small example because my aim is to collect all FROM numbers but without any redundancy. </p>