Re: Jesus, what have I done (was: LONG) - Mailing list pgsql-hackers

From wieck@debis.com (Jan Wieck)
Subject Re: Jesus, what have I done (was: LONG)
Date
Msg-id m11x6nh-0003kGC@orion.SAPserv.Hamburg.dsh.de
Whole thread Raw
In response to Re: Jesus, what have I done (was: LONG)  (Bruce Momjian <pgman@candle.pha.pa.us>)
Responses Re: [HACKERS] Re: Jesus, what have I done (was: LONG)
Re: [HACKERS] Re: Jesus, what have I done (was: LONG)
Re: [HACKERS] Re: Jesus, what have I done (was: LONG)
List pgsql-hackers
> >     No I won't. As explained, I would return a tuple as is,  just
> >     with  the  LONG reference information. It will only, but then
> >     allways again, be expanded if needed to compare, store  again
> >     or  beeing output to the client.  This "allways again" is one
> >     of my drawbacks against your "treating all varsize  pushable"
> >     concept.  In  one  of  my  early  projects, I had to manage a
> >     microVax for a year, and I love  systems  that  can  be  fine
> >     tuned  since  then, really! Auto detection is a nice feature,
> >     but if that failes and you don't have  any  override  option,
> >     you're hosed.
>
> I am confused here.  With my code, you only have to:
>
>    add code to write/read from long tables
>    add code to expand long values in varlen access routines
>    add code to heap_insert() to move data to long tables
>    add code to heap_delete() to invalidate long tuples

    Add  code  to  expand  long values in varlen access routines,
    you're joking - no?

    How many functions are there, called  via  the  fmgr  with  a
    Datum as argument, and only knowing by themself (and a system
    catalog) that they receive a variable length attribute?

    So you would better do the fetching in the fmgr. Then  again,
    there  are  many  places  in  the  code (and possibly in user
    extensions too), that call builtin functions  like  textout()
    directly, passing it the Datum they got from somewhere.

    I can understand why you would like to automatically pull out
    varsize values as  needed.  But  I  see  really  a  bunch  of
    problems coming with it.


Jan

--

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