(PHP 4 >= 4.2.0, PHP 5)
pg_lo_seek — Seeks position within a large object
$large_object
, int $offset
[, int $whence = PGSQL_SEEK_CUR
] )pg_lo_seek() seeks a position within a large object resource.
To use the large object interface, it is necessary to enclose it within a transaction block.
large_object
PostgreSQL large object (LOB) resource, returned by pg_lo_open().
offset
The number of bytes to seek.
whence
One of the constants PGSQL_SEEK_SET (seek from object start),
PGSQL_SEEK_CUR (seek from current position)
or PGSQL_SEEK_END (seek from object end) .
Returns TRUE on success or FALSE on failure.
Example #1 pg_lo_seek() example
<?php
$doc_oid = 189762345;
$database = pg_connect("dbname=jacarta");
pg_query($database, "begin");
$handle = pg_lo_open($database, $doc_oid, "r");
// Skip first 50000 bytes
pg_lo_seek($handle, 50000, PGSQL_SEEK_SET);
// Read the next 10000 bytes
$data = pg_lo_read($handle, 10000);
pg_query($database, "commit");
echo $data;
?>