title: POSTGRES - Risk of dropping foreign data wrapper/schema
body: <p>We had one of the devs create a foreign data wrapper with these commands:</p>
  
  <pre><code>CREATE SERVER serverName FOREIGN DATA WRAPPER postgres_fdw OPTIONS (xxxx);
  CREATE USER MAPPING FOR user SERVER foreign_db OPTIONS (user 'xxxx', password 'xxxx');
  CREATE SCHEMA foreign_db;
  IMPORT FOREIGN SCHEMA public FROM SERVER serverName INTO foreign_db;
  </code></pre>
  
  <p>To drop this schema the suggestion was to run:</p>
  
  <pre><code>DROP SCHEMA if exists foreign_db cascade;
  DROP USER mapping if exists for user server foreign_db;
  DROP SERVER if exists serverName;
  </code></pre>
  
  <p>In the spec I see this for CASCADE:</p>
  
  <blockquote>
    <p>Automatically drop objects (tables, functions, etc.) that are
    contained in the schema, and in turn all objects that depend on those
    objects</p>
  </blockquote>
  
  <p>what concerns me is this line:</p>
  
  <pre><code>and in turn all objects that depend on those objects 
  </code></pre>
  
  <p>My question is there a possibility of dropping anything outside of <strong>foreign_db</strong> schema and if yes, how can I check it? </p>
  
  <p>Thank you.</p>