Referring to tuplesort.c   and    tuplestore.c

BACKGROUND: Starting from dumptuples() [ tuplesort.c ] write functions move the tuple from a buffer to another in order to finally write it in a logical tape. Is there a way (even the most inefficient way) to use current read/write functions provided by PostgreSQL in order to retrieve the first tuple of a certain run while performing External Sorting?

NOTE: I need the first tuple in order to manipulate the whole corresponding run, tuple by tuple since they are written sequentially in a run.

Thanks for your attention.
Regards, Manolo.


--------------------------------------------------
From: <[EMAIL PROTECTED]>
Sent: Tuesday, February 26, 2008 4:10 PM
To: "Jaime Casanova" <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]>
Cc: "Decibel!" <[EMAIL PROTECTED]>; "David Fetter" <[EMAIL PROTECTED]>; <pgsql-patches@postgresql.org>; <[EMAIL PROTECTED]>
Subject: Re: [HACKERS] [PATCHES] 2WRS [WIP]

For the joy of all of you: that's the correct WIP patch.
At the moment it only tries to create runs uding two heaps. Hope you can
help me with writing those runs on tapes.

I'd be very pleased to give you more details.

Thenks for your time.
Regards, Manolo.


--------------------------------------------------
From: "Jaime Casanova" <[EMAIL PROTECTED]>
Sent: Friday, February 22, 2008 5:30 AM
To: <[EMAIL PROTECTED]>
Cc: "Decibel!" <[EMAIL PROTECTED]>; "Manolo _" <[EMAIL PROTECTED]>;
"David Fetter" <[EMAIL PROTECTED]>; <pgsql-patches@postgresql.org>;
<[EMAIL PROTECTED]>
Subject: Re: [HACKERS] [PATCHES] 2WRS [WIP]

On Thu, Feb 21, 2008 at 6:44 AM,  <[EMAIL PROTECTED]> wrote:
Hi.

That's the last release and refers to 8.3.0 and not to 8.2.5 as before.
Hope
you can tell me if I created it correctly please.


no, it doesn't...

! /* GUC variables */
  #ifdef TRACE_SORT
  bool trace_sort = false;
  #endif
- #ifdef DEBUG_BOUNDED_SORT
- bool optimize_bounded_sort = true;
- #endif

it's seems you're removing something added in 8.3

--
regards,
Jaime Casanova

"Programming today is a race between software engineers striving to
build bigger and better idiot-proof programs and the universe trying
to produce bigger and better idiots.
So far, the universe is winning."
Richard Cook

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