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Re: is there better way than the call a function twice.

From: Stephane Faroult <sfaroult_at_roughsea.com>
Date: Wed, 3 Nov 2004 10:47:39 +0100
Message-Id: <200411030947.iA39ldf9023315@webmail.nexlink.net>

 

I usually try to get rid of function calls, especially costly ones, in SQL statements but when everything fails I try to use packaged variables, eg

create package wrapper

as

    function ugly_func(param in some_type)

    return whatever;

end;

create package body wrapper

as

   hidden_var                    whatever; 

   previous_parameter      some_type := NULL; 

   function ugly_func(param in some_type)    return whatever
   is
   begin

     if (param = previous_parameter)
     then
        --  Unless the function calls a random function ...
        return hidden_var;

    end if;
    hidden_var := ugly_function(param);
    previous_parameter := param;
    return hidden_var;
  end;
end;

and replace calls to ugly_function with calls to wrapper.ugly_func.

Regards,

Stephane Faroult

RoughSea Ltd
http://www.roughsea.com

On Tue, 2 Nov 2004 16:49 , 'Duret, Kathy' <kduret_at_starkinvestments.com> sent:

oh magic eight ball is there a better way than calling a ugly function twice when I need two columns returned with the same value.

I hate the call the function twice because it is very costly.

what I need to do is:
select x,y,z, ugly_function as ugly1, ugly_function ugly2 from a

when I do.... it actually gives me worse results ie. more physical reads....

select x,y,z , ugly1, ugly1 as ugly2 from ( select x,y,z, ugly_function ugly1 from a)

Is there anyway around this?

Kathy.

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Received on Wed Nov 03 2004 - 03:31:57 CST

Original text of this message

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