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pg_lo_seek

(PHP 4 >= 4.2.0, PHP 5)

pg_lo_seek — Seeks position within a large object

Descrierea

bool pg_lo_seek ( resource $large_object , int $offset [, int $whence ] )

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.

Parametri

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) .

Valorile întroarse

Întoarce valoarea TRUE în cazul succesului sau FALSE în cazul eşecului.

Exemple

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($handle50000PGSQL_SEEK_SET);
   
// Read the next 10000 bytes
   
$data pg_lo_read($handle10000);
   
pg_query($database"commit");
   echo 
$data;
?>

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