Re: PL/pgSQL examples NOT involving functions

Поиск
Список
Период
Сортировка
От Jan Wieck
Тема Re: PL/pgSQL examples NOT involving functions
Дата
Msg-id 200112052126.fB5LQlp01967@saturn.jw.home
обсуждение исходный текст
Ответ на Re: PL/pgSQL examples NOT involving functions  ("Aasmund Midttun Godal" <postgresql@envisity.com>)
Список pgsql-sql
Aasmund Midttun Godal wrote:
> Erm, sorry about the multiple postings, I just discovered a couple of interesting tidbits after I posted first...
>
> http://www.postgresql.org/idocs/index.php?plpgsql.html :
>
> "The PL/pgSQL call handler parses the function's source text and produces an internal binary instruction tree the
firsttime the function is called."
 
   And  that  is  still  not  entirely  accurate.  At  the first   function call  the  control  language  (IF,  WHEN,
etc.) is   parsed.  All  expressions  and queries are just remembered as   strings with variables replaced by $n
parameters. Now  every   statement will prepare a saved plan the first time it is hit.
 
   So when you have a  function  with  conditional  code  and  a   specific  branch of that code is never called, the
statements  in there will never be prepared.
 


Jan

--

#======================================================================#
# It's easier to get forgiveness for being wrong than for being right. #
# Let's break this rule - forgive me.                                  #
#================================================== JanWieck@Yahoo.com #



_________________________________________________________
Do You Yahoo!?
Get your free @yahoo.com address at http://mail.yahoo.com



В списке pgsql-sql по дате отправления:

Предыдущее
От: Martín Marqués
Дата:
Сообщение: Re: INT OR VARCHAR
Следующее
От: Jan Wieck
Дата:
Сообщение: Re: PL/pgSQL examples NOT involving functions