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From: michael dot peppler at bnpparibas dot com
Subject: Re: I must be doing something wrong... (reading image data with DBD::Sybase)
Date: Jun 1 2007 9:26AM


I just tried it here (using the test script t/xblob.t as a sample) with no 

$dbh->{LongReadLen} = 100000;
$sth = $dbh->prepare("select id, data from blob_test");
$sth->{syb_no_bind_blob} = 1;
while(my $d = $sth->fetch) {
    my $data;
    my $read = $sth->syb_ct_get_data(2, \$data, 0);
    print "read = $read\n";


And I get:

[pepm01a@gvas1tkc6001 DBD-Sybase-1.08]$ perl test/
read = 96804

Maybe a run with DBI->trace(5) could give us some more information...


Internet - 01.06.2007 10:41
Please respond to
Sent by:
To:     sybperl-l
Subject:        I must be doing something wrong... (reading image data 
with DBD::Sybase)

Folks, I've looked everywhere but I cannot find the error I'm no doubt
In short, I'm unable to read more than 32768 bytes from an image column,
although I've followed -afaik- all the required steps.

I've verified that the image stored in the image column is indeed bigger
than 32Kb (with datalength()). However, I'm getting only the first 32KB

My code:

$dbh->{LongReadLen} = 10000000;

$sth = $dbh->prepare("select img_col from my_table where id = 12345 ");
$sth->{syb_no_bind_blob} = 1;

while(my $d = $sth->fetch) {
$size = $sth->syb_ct_get_data(1, \$my_img, 0);

....which returns only 32KB.

However, when I select @@textsize prior to the prepare(), this returns
32768. In fact, I replaced setting LongReadLen with 'set textsize
10000000', and this does not change things: select @@textsize then still
returns only the first 32KB. I've verified through the MDA table
monSysSQLText that 'set textsize 10000000' is actually executed, so it
beats why @@textsize is still set to 32768.

Any hints appreciated!


Rob V.

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