
   <code class="command">ALTER OPERATOR FAMILY</code>, they are not part of any
   specific operator class within the family, but are just <span class="quote">“<span class="quote">loose</span>”</span>
   within the family.  This indicates that these operators and functions
   are compatible with the family's semantics, but are not required for
   correct functioning of any specific index.  (Operators and functions
   that are so required should be declared as part of an operator class,
   instead; see 