I see only 2 alternatives there, either append text to a blob directly, or
append to a text variable and then move it to a blob.
I ran a quick test using both alternatives, and a series of TEXT TO BLOB is
more than 10x faster then appending to a text variable and then moving it to a
blob.
Code is attached. Testing with smaller repeat counts yields basically no
difference. With a large repeat count then we are talking about 20ms (blob)
against 287ms (text). Running compiled.
hth
julio
> On Aug 1, 2017, at 7:22 AM, David Adams via 4D_Tech <4d_tech@lists.4d.com>
> wrote:
>
> Thanks for the answer! I was not clear in my question :( I'm calling a
> command in the PostgreSQL plug-in like this:
>
> PgSQL Send Copy Data( connection id ; data in a blob ; rowCount ) →
> result
>
> The second argument contains the data you're sending, and it has to be
> passed into the plug-in as a BLOB. Presumably, this is because the plug-in
> supports very old versions of 4D that had a 32,000 character limit on text
> values. My source data consists of strings and longints, but I need to get
> it into a BLOB.
>
> This plug-in command is making it easy to call the Postgres COPY IN
> command. That's Postgres' native bulk loader. I'm likely to be transferring
> millions of rows at a time, so high-speed bulk loading is of real interest.
> These days it's rare that I find the need to worry about optimizing
> operations but, in this case, it is necessary.
>
> So, with that background, I'm asking about the fastest way to load up a
> BLOB...if that's even a meaningful question and if anyone has advice.
>
> Thanks!
--
Julio Carneiro
jjfo...@gmail.com
===============================
C_LONGINT($start;$time1;$time2;$i)
C_BLOB($blob1;$blob2)
C_TEXT($text)
SET BLOB SIZE($blob;0)
$start:=Milliseconds
For ($i;1;10000)
TEXT TO BLOB("abcdefghijklmnopqrstuvwxyz01234567890";$blob1;UTF8 text
without length;*)
End for
$time1:=Milliseconds-$start
SET BLOB SIZE($blob2;0)
$text:=""
$start:=Milliseconds
For ($i;1;10000)
$text:=$text+"abcdefghijklmnopqrstuvwxyz01234567890"
End for
TEXT TO BLOB($text;$blob;UTF8 text without length)
$time2:=Milliseconds-$start
ALERT("Add to Blob:"+String($time1)+"\nAdd to Text:"+String($time2))
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