and binary output is determined by the format
     codes given in Bind, regardless of the SQL command involved.  The
     <literal>BINARY</literal> attribute in cursor declarations is irrelevant when
     using extended query protocol.
    </para>
   </note>

   <para>
    Query planning typically occurs when the Bind message is processed.
    If the prepared statement has no parameters, or is executed repeatedly,
    the server might save the created plan and re-use it during subsequent
    Bind messages for the same prepared statement.  However, it will do so
    only if it finds that a generic plan can be created that is not much
    less efficient than a plan that depends on the specific parameter values
    supplied.  This happens transparently so far as the protocol is concerned.
   </para>

   <para>
    If successfully created, a named portal object lasts till the end of the
    current transaction, unless explicitly destroyed.  An unnamed portal is
    destroyed at the end of the transaction, or as soon as the next Bind
    statement specifying the unnamed portal as destination is issued.  (Note
    that a simple Query message also destroys the unnamed portal.)  Named
    portals must be explicitly closed before they can be redefined by another
    Bind message, but this is not required for the unnamed portal.
    Named portals can also be created and accessed at the SQL
    command level, using <command>DECLARE CURSOR</command> and <command>FETCH</command>.
   </para>

   <para>
    Once a portal exists, it can be executed using an Execute message.
    The Execute message specifies the portal name (empty string denotes the
    unnamed portal) and
    a maximum result-row count (zero meaning <quote>fetch all rows</quote>).
    The result-row count is only meaningful for portals
    containing commands that return row sets; in other cases the command is
    always executed to completion, and the row count is ignored.
    The possible
    responses to Execute are the same as those described above for queries
    issued via simple query protocol, except that Execute doesn't cause
    ReadyForQuery or RowDescription to be issued.
   </para>

   <para>
    If Execute terminates before completing the execution of a portal
    (due to reaching a nonzero result-row count), it will send a
    PortalSuspended message; the appearance of this message tells the frontend
    that another Execute should be issued against the same portal to
    complete the operation.  The CommandComplete message indicating
    completion of the source SQL command is not sent until
    the portal's execution is completed.  Therefore, an Execute phase is
    always terminated by the appearance of exactly one of these messages:
    CommandComplete, EmptyQueryResponse (if the portal was created from
    an empty query string), ErrorResponse, or PortalSuspended.
   </para>

   <para>
    At completion of each series of extended-query messages, the frontend
    should issue a Sync message.  This parameterless message causes the
    backend to close the current transaction if it's not inside a
    <command>BEGIN</command>/<command>COMMIT</command> transaction block (<quote>close</quote>
    meaning to commit if no error, or roll back if error).  Then a
    ReadyForQuery response is issued.  The purpose of Sync is to provide
    a resynchronization point for error recovery.  When an error is detected
    while processing any extended-query message, the backend issues
    ErrorResponse, then reads and discards messages until a Sync is reached,
    then issues ReadyForQuery and returns to normal message processing.
    (But note that no skipping occurs if an error is detected
    <emphasis>while</emphasis> processing Sync &mdash; this ensures that there is one
    and only one ReadyForQuery sent for each Sync.)
   </para>

   <note>
    <para>
     Sync does not cause a transaction block opened with <command>BEGIN</command>
     to be closed.  It is possible