Fetching BLOB via PDO odbc is missing parts of the result

Description

We're trying to stream an image from our IBM i filesystem (IFS) by fetching a blob via PDO. However the result is missing half the blob in a repeating pattern.

The following code:

$db = new PDO("odbc:DSN=NAME", 'user', 'pass');
$stmt = $db->prepare("SELECT * FROM TABLE(QSYS2.IFS_READ_BINARY('/path/to/file.jpg'))");
$stmt->execute();
$stmt->bindColumn(1, $type, PDO::PARAM_STR, 256);
$stmt->bindColumn(2, $lob, PDO::PARAM_LOB);
$stmt->fetch(PDO::FETCH_BOUND);

Resulted in this output:

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

But I expected this output instead:

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

Comparing the two results below, we see the missing parts highlighted in blue:

We do get the right result using the same driver and query in different languages/ applications so it seems to be a problem in php odbc or PDO.
It also doesn't matter what file we try to stream.

PHP Version

PHP 8.1.5

Operating System

No response

まず、PHP 8.1.5 上で PDO::bindColumn(PDO::PARAM_LOB) と PDO::fetch(PDO::FETCH_BOUND) を使って、示されている PDO ODBC クエリを再現し、次に PDO ODBC の BLOB 取得パスを調査します。完了条件は、報告で見られた繰り返し発生する欠落セクションなしに、完全な BLOB が返されることです。