Re: Patch to add a primary key using an existing index

In the end I think this is mainly an issue of setting appropriate
expectations in the documentation.  I've added the following text to
the ALTER TABLE manual page:

    <para>
     After this command is executed, the index is <quote>owned</> by the
     constraint, in the same way as if the index had been built by
     a regular <literal>ADD PRIMARY KEY</> or <literal>ADD UNIQUE</>
     command.  In particular, dropping the constraint will make the index
     disappear too.
    </para>