PostgreSQL Functions
PHP Manual

pg_lo_seek

Seeks position within a large object

Description

bool pg_lo_seek ( resource $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.

Parameters

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) .

Return Values

Returns TRUE on success or FALSE on failure.

Examples

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;
?>

Changelog

Version Description
5.6.0 Added PostgreSQL 9.3's 64bit large object support. Both client and server must support PostgreSQL 9.3 and PHP must be 64bit build to use 64bit large object.

See Also

  • pg_lo_tell