ists
    mainly for the syntactic convenience of making message generation
    look like a single function call in the C source code.  The only parameter
    accepted directly by <code class="function">ereport</code> is the severity level.
    The primary message text and any optional message elements are
    generated by calling auxiliary functions, such as <code class="function">errmsg</code>,
    within the <code class="function">ereport</code> call.
   </p><p>
    A typical call to <code class="function