title: read TNSNAMES Contents with sql-statement
body: <p>There is a way to read the Definitions in current tnsname with sql-statement?</p>
  
  <p>For example, my current tnsnames.ora contain follows:</p>
  
  <pre><code>MYSID_MYSERVER =
    (DESCRIPTION =
      (ADDRESS_LIST =
        (ADDRESS = (PROTOCOL = TCP)(HOST = myserver.abc.com)(PORT = 1521))
      )
      (CONNECT_DATA =
        (SERVER = DEDICATED)
        (SID = mysid)
      )
    )
  </code></pre>
  
  <p>Of course, I can do</p>
  
  <pre><code>$SQL  conn scott@MYSID_MYSERVER
  </code></pre>
  
  <p>I will know, if I can read the properties of "MYSID_MYSERVER", for example with a system-view</p>
  
  <pre><code>$SQL select * from TNSNAME_V
  </code></pre>
  
  <p>or if I can get the "HOST" Attribute connected with "MYSID_MYSERVER"</p>