Message-Id: <10666.120730@fatcity.com> From: "Veera Prasad" Date: Tue, 31 Oct 2000 15:27:51 -0500 Subject: Re: direct =y in export statement --------------E034CD1F8456B5CC0AE3A407 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit 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? --------------E034CD1F8456B5CC0AE3A407 Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: 7bit 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?