Re: direct =y in export statement

From: Veera Prasad <vprasad_at_olf.com>
Date: Tue, 31 Oct 2000 15:27:51 -0500
Message-Id: <10666.120730@fatcity.com>

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In Conventional path:
Conventional path Export uses the SQL SELECT statement to extract data from tables. Data is read from disk into a buffer cache, and rows are transferred
to the evaluating buffer. The data, after passing expression evaluation, is
transferred to the Export client, which then writes the data into the export file.

In Direct path:
Direct path Export extracts data much faster than a conventional path export.
Direct path Export achieves this performance gain by reading data directly,
bypassing the SQL command processing layer and saves on data copies whenever possible.

In a direct path Export, data is read from disk into the buffer cache and rows
are transferred directly to the Export client. The evaluating buffer is bypassed.
The data is already in the format that Export expects, thus avoiding unnecessary
data conversion. The data is transferred to the Export client, which then writes
the data into the export file.

Veera
Note: I did cut and paste from documentation.

Swapna_P wrote:

>
>
> what does this indicate?
> what is its significance?

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In Conventional path:
 Conventional path Export uses the SQL SELECT statement to extract data
 from tables. Data is read from disk into a buffer cache, and rows are
transferred
 to the evaluating buffer. The data, after passing expression evaluation,
is
 transferred to the Export client, which then writes the data into the
export file.
In Direct path:
 Direct path Export extracts data much faster than a conventional path
export.
 Direct path Export achieves this performance gain by reading data directly,
 bypassing the SQL command processing layer and saves on data copies
 whenever possible.
In a direct path Export, data is read from disk into the buffer cache
and rows
 are transferred directly to the Export client. The evaluating buffer
is bypassed.
 The data is already in the format that Export expects, thus avoiding
unnecessary
 data conversion. The data is transferred to the Export client, which
then writes
 the data into the export file.
Veera
 Note: I did cut and paste from documentation.
Swapna_P wrote:
<blockquote TYPE=CITE> 
what does this indicate?
 what is its significance?</blockquote>
Received on Tue Oct 31 2000 - 14:27:51 CST