aves prepared statements
    and sometimes execution plans in this way,
    SQL commands that appear directly in a
    <SPAN
CLASS="APPLICATION"
>PL/pgSQL</SPAN
> function must refer to the
    same tables and columns on every execution; that is, you cannot use
    a parameter as the name of a table or column in an SQL command.  To get
    around this restriction, you can construct dynamic commands using
    the <SPAN
CLASS="APPLICATION"
>PL/pgSQL</SPAN
> <TT
CLASS="COMMAND"
>EXECUTE</TT
>
    statement &md