title: Oracle SQL Invalid Identifier
body: <p>I'm trying to run this query but I get "ORA-00904: "Z1"."LONGITUDE": invalid identifier"</p>
  
  <p>Is there a way to rewrite this so I have access to that column in the exists subquery?  Or is there generally a better way to achieve what I'm trying to do?</p>
  
  <p>Thanks</p>
  
  <pre><code>select zip, count(UNIQUE address_id) LOCATIONS
  from records 
  inner join addresses a using(address_id) 
  inner join zip_coords z1 using(zip)
  where exists
  (
    select 1 from (
      select distance(z1.latitude, z1.longitude, z2.latitude, z2.longitude) d
      from zip_coords z2
      where z2.zip in (
        select zip from available_zips
      )
    ) where d &lt;= 50
  )
  GROUP BY ZIP
  </code></pre>