PDO::pgsqlLOBCreate - Creates a new large object
Вернуться к: PostgreSQL (PDO)
PDO::pgsqlLOBCreate
(PHP 5 >= 5.1.2, PHP 7, PECL pdo_pgsql >= 1.0.2)
PDO::pgsqlLOBCreate — Creates a new large object
Описание
PDO::pgsqlLOBCreate() creates a large object and returns the OID of that object. You may then open a stream on the object using PDO::pgsqlLOBOpen() to read or write data to it. The OID can be stored in columns of type OID and be used to reference the large object, without causing the row to grow arbitrarily large. The large object will continue to live in the database until it is removed by calling PDO::pgsqlLOBUnlink().
Large objects can be up to 2GB in size, but are cumbersome to use; you need to ensure that PDO::pgsqlLOBUnlink() is called prior to deleting the last row that references its OID from your database. In addition, large objects have no access controls. As an alternative, try the bytea column type; recent versions of PostgreSQL allow bytea columns of up to 1GB in size and transparently manage the storage for optimal row size.
Замечание: This function must be called within a transaction.
Список параметров
PDO::pgsqlLOBCreate() takes no parameters.
Возвращаемые значения
Returns the OID of the newly created large object on success, or FALSE
on failure.
Примеры
Пример #1 A PDO::pgsqlLOBCreate() example
This example creates a new large object and copies the contents of a file into it. The OID is then stored into a table.
<?php
$db = new PDO('pgsql:dbname=test host=localhost', $user, $pass);
$db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$db->beginTransaction();
$oid = $db->pgsqlLOBCreate();
$stream = $db->pgsqlLOBOpen($oid, 'w');
$local = fopen($filename, 'rb');
stream_copy_to_stream($local, $stream);
$local = null;
$stream = null;
$stmt = $db->prepare("INSERT INTO BLOBS (ident, oid) VALUES (?, ?)");
$stmt->execute(array($some_id, $oid));
$db->commit();
?>
Смотрите также
- PDO::pgsqlLOBOpen() - Opens an existing large object stream
- PDO::pgsqlLOBUnlink() - Deletes the large object
- pg_lo_create() - Создает большой объект
Вернуться к: PostgreSQL (PDO)