Paul,
I have been interested in testing this out myself, so in the interests of all I 
just ran a test inserting a 2,000,000 record table into another table with an 
integer PK index and a 20 character index (ID field) and the SQL Insert runs 
75% quicker but only 25% quicker if the "select(" (suggested by Alan) for the 
inserted records is either a physical table or a readwrite cursor.

I suppose this confirms that using cursors to pre-fetch your data into memory 
is significantly faster for insertions as the required records are either in 
memory completely or filtered by VFP. As we all know making a cursor readwrite 
effectively makes a cursor perform the same as a physical table as it causes 
VFP to create a physical "table" which would appear to significantly degrade 
performance - understandable.

Hope this makes sense... have to go, made myself late for dinner, so if not 
I'll explain better tomorrow!!

Dave Crozier
Software Development Manager
Flexipol Packaging Ltd.



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-----Original Message-----
From: ProFox <profox-boun...@leafe.com> On Behalf Of Paul H. Tarver
Sent: 12 April 2018 14:19
To: profox@leafe.com
Subject: RE: Appending from a Cursor

Ok, so let me ask the $64,000 question: Which method is faster or better:
Append From DBF( or Insert Into as Gene used?

I have a similar project were I am issuing the same query to multiple SQL 
databases/servers and then using the Append From DBF( command to aggregate the 
results from each individual query into a large, single cursor to use for 
actual processing.

I'm traveling today or I'd test this myself, but I have limited access.
Figured I'd see if anyone else had already determined the best choice before I 
go poking around on my own.

Paul

-----Original Message-----
From: ProfoxTech [mailto:profoxtech-boun...@leafe.com] On Behalf Of Ted Roche
Sent: Thursday, April 12, 2018 6:18 AM
To: profoxt...@leafe.com
Subject: Re: Appending from a Cursor

On Wed, Apr 11, 2018 at 8:31 PM, Gene Wirchenko <ge...@telus.net> wrote:
>
>      I am puzzled why (alimport) works for the SQL but not the append
from,
> but whatever.
>

I agree with you that it is un-intuitive that aliases work *almost* everywhere. 
It's one of those hundreds of FoxPro's "always been that way" things.

As others have said, APPEND FROM is ancient nearly-original XBase.
While it was updated occasionally for new file formats, the main purpose of the 
command is a low-level IMPORT (sibling command) from foreign formats and not as 
a cursor-manipulation command, so it's intended for reading files-on-disk and 
not cursors.


--
Ted Roche
Ted Roche & Associates, LLC
http://www.tedroche.com

[excessive quoting removed by server]

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