title: psql indicates different server version
body: <p>Today I was prompted to upgrade my OS from Ubuntu 14.04 LTS to 16.04 LTS.  Generally speaking, it went smoothly.  However, I did receive error messages indicating that the upgrade of PostgreSQL from 9.3 to 9.5 did not succeed.  I eventually was able to install postgresql-9.5 and have verified that I see my previously created databases and tables.</p>
  
  <p>However, when I use the <code>psql</code> command to access a database called <code>hierarchy</code> as follows, I get some unfamiliar output:</p>
  
  <pre><code>$ psql hierarchy jkeenan
  psql (9.5.3, server 9.3.13)
  Type "help" for help.
  </code></pre>
  
  <p>Does this indicate that part of my PostgreSQL setup (broadly speaking) was <strong>not</strong> upgraded to 9.5?</p>
  
  <p><strong>Update:</strong>  Once inside <code>psql</code> I can say <code>SELECT version();</code> and get this output:</p>
  
  <pre><code> PostgreSQL 9.3.13 on x86_64-unknown-linux-gnu, compiled by gcc (Ubuntu 4.8.4-2ubuntu1~14.04.1) 4.8.4, 64-bit
  </code></pre>
  
  <p>How would I perform this upgrade?  Is the difference between the <code>psql</code> version and the "server" version something I should be concerned about?</p>
  
  <p>Other data which might be helpful in diagnosis:</p>
  
  <pre><code>$ createdb --version
  createdb (PostgreSQL) 9.5.3
  $ psql --version
  psql (PostgreSQL) 9.5.3
  </code></pre>
  
  <p>Thank you very much.</p>