PDO::pgsqlLOBOpen

Opens an existing large object stream

Description

public resourcefalse PDO::pgsqlLOBOpen(string $oid, string $mode = "rb")

PDO::pgsqlLOBOpen opens a stream to access the data referenced by oid. If mode is r, the stream is opened for reading, if mode is w, then the stream will be opened for writing. You can use all the usual filesystem functions, such as fread, fwrite and fgets to manipulate the contents of the stream.

Note: This function, and all manipulations of the large object, must be called and carried out within a transaction.

Parameters

oid

A large object identifier.

mode

If mode is r, open the stream for reading. If mode is w, open the stream for writing.

Return Values

Returns a stream resource on success or false on failure.

Examples

Example #1 A PDO::pgsqlLOBOpen example

Following on from the PDO::pgsqlLOBCreate example, this code snippet retrieves the large object from the database and outputs it to the browser.

<?php
$db = new PDO('pgsql:dbname=test host=localhost', $user, $pass);
$db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$db->beginTransaction();
$stmt = $db->prepare("select oid from BLOBS where ident = ?");
$stmt->execute(array($some_id));
$stmt->bindColumn('oid', $oid, PDO::PARAM_STR);
$stmt->fetch(PDO::FETCH_BOUND);
$stream = $db->pgsqlLOBOpen($oid, 'r');
header("Content-type: application/octet-stream");
fpassthru($stream);
?>

See Also

  • PDO::pgsqlLOBCreate
  • PDO::pgsqlLOBUnlink
  • pg_lo_open