pg_end_copy
To prevent any problems with encoding you could use hexadecimal or base64 input to save and retrieve data to the database:
<?php
// Connect to the database
$dbconn = pg_connect( 'dbname=foo' );
// Read in a binary file
$data = file_get_contents( 'image1.jpg' );
// Escape the binary data
$escaped = bin2hex( $data );
// Insert it into the database
pg_query( "INSERT INTO gallery (name, data) VALUES ('Pine trees', decode('{$escaped}' , 'hex'))" );
// Get the bytea data
$res = pg_query("SELECT encode(data, 'base64') AS data FROM gallery WHERE name='Pine trees'");
$raw = pg_fetch_result($res, 'data');
// Convert to binary and send to the browser
header('Content-type: image/jpeg');
echo base64_decode($raw);
?>
pg_escape_bytea
(PHP 4 >= 4.2.0, PHP 5)
pg_escape_bytea — Gera binários para o tipo bytea
Descrição
string pg_escape_bytea
( string
$data
)pg_escape_bytea() gera uma string do tipo bytea. Retorna uma string com escapes.
Nota:
Quando você usa SELECT bytea type, o PostgreSQL retorna valores de byte octais prefixados por \ (ex.: \032). Usuários devem converter de volta para binários por si mesmos.
Esta função exige PostgreSQL 7.2 ou superior. Com PostgreSQL 7.2.0 e 7.2.1, o tipo de dados bytea deve ser criado quando você habilita o suporte a multi-byte. Por exemplo, INSERT INTO tabela_teste (imagem) VALUES ('$imagem_escaped'::bytea); PostgreSQL 7.2.2 ou superior não precisa de coerção (cast). A exceção é quando a codificação de caracteres do cliente e do backend não combinam, então pode haver erro de fluxo de multi-byte. O usuário deve fazer a coerção (cast) para bytea para evitar este erro.
Veja também: pg_unescape_bytea() e pg_escape_string().
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User Contributed Notes
pg_escape_bytea - [5 notes]
Mike-RaWare ¶
2 years ago
gglockner AT NOSPAMdwaffler DOT com ¶
3 years ago
If you're getting errors about nonstandard use of \\ in a string literal, then you need to escape the encoded bytea as follows:
<?php
$escaped = pg_escape_bytea($data);
pg_query("INSERT INTO gallery (name, data) VALUES ('Pine trees', E'$escaped'::bytea)");
?>
ynzhang from lakeheadu of ca ¶
4 years ago
The reason pg_unescape_bytea() do not exactly reproduce the binary data created by pg_escape_bytea() is because the backslash \ and single quote ' are double escaped by the pg_escape_bytea() function. This will lead to image seems corrupted when retrieve from the bytea field. The proper way to escape&unescape a binary string into a PG bytea field as follow:
<?php
$escaped_data = str_replace(array("\\\\", "''"), array("\\", "'"), pg_escape_bytea($data));
/* and later unescape the escaped data from the bytea field with following to get the original binary data */
$original_data = pg_unescape_bytea($escaped_data));
?>
more details at: http://archives.postgresql.org/pgsql-php/2007-02/msg00014.php
Mocha ¶
9 years ago
to unescape_bytea use stripcslashes(). If you need to escape bytea and don't have pg_escape_bytea() function then use:
<?php
function escByteA($binData) {
/**
* \134 = 92 = backslash, \000 = 00 = NULL, \047 = 39 = Single Quote
*
* str_replace() replaces the searches array in order. Therefore, we must
* process the 'backslash' character first. If we process it last, it'll
* replace all the escaped backslashes from the other searches that came
* before.
*/
$search = array(chr(92), chr(0), chr(39));
$replace = array('\\\134', '\\\000', '\\\047');
$binData = str_replace($search, $replace, $binData);
return $binData;
//echo "<pre>$binData</pre>";
//exit;
}
?>
php at tobias dot olsson dot be ¶
10 years ago
if you need to change back bytea from the db to normal data, this will do that:
<?php
function pg_unescape_bytea($bytea) {
return eval("return \"".str_replace('$', '\\$', str_replace('"', '\\"', $bytea))."\";");
}
// use like this
$rs = pg_query($conn, "SELECT image from images LIMIT 1");
$image = pg_unescape_bytea(pg_fetch_result($rs, 0, 0));
?>
/Tobias