PL/pgSQL / SPI and UTILITY statements

Hi,

    there  was  recently discussion about schema changes (utility
    queries) inside of PL functions etc.

    I've thought about it some more and came  to  the  conclusion
    that  it  doesn't  make  much sense to support something like
    that in PL/pgSQL.

    The reason for this is that PL/pgSQL does  prepare  and  save
    ALL  plans on the first call of the function. As it is now, a
    PL/pgSQL function used once in a connection will  get  broken
    if  an  object  it uses gets dropped and recreated. The saved
    SPI plans still use the OLD object, which isn't available any
    more.  So  the  function needs to be recompiled and that will
    only happen on a new backend connection.

    There is no syntax that could tell PL/pgSQL  not  to  save  a
    particular  prepared  plan (like in PL/Tcl where planning and
    saving is done separately,  so  the  programmer  has  control
    which plans to save and which not).

    Since  dropping  an  object  in Postgres is a general problem
    that affects saved SPI plans (not  only  in  PL,  C  language
    functions  using  the SPI saved plan feature will break too),
    I'll not add support for it to PL/pgSQL. I think this problem
    will  also  show up if any function using prepared plans will
    be used on the temp tables Bruce currently is working on.




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