<?php
/**
* DbSimple_Postgreql: PostgreSQL database.
* (C) 2005 Dmitry Koterov, http://forum.dklab.ru/users/DmitryKoterov/
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
* See http://www.gnu.org/copyleft/lesser.html
*
* Placeholders are emulated because of logging purposes.
*
* @version 2.x $Id: Postgresql.php 64 2006-12-18 16:38:40Z dk $
*/
require_once dirname(__FILE__) . '/Generic.php';
/**
* Database class for PostgreSQL.
*/
class DbSimple_Postgresql extends DbSimple_Generic_Database
{
var $DbSimple_Postgresql_USE_NATIVE_PHOLDERS = null;
var $prepareCache = array();
var $link;
/**
* constructor(string $dsn)
* Connect to PostgresSQL.
*/
function DbSimple_Postgresql($dsn)
{
$p = DbSimple_Generic::parseDSN($dsn);
if (!is_callable('pg_connect')) {
return $this->_setLastError("-1", "PostgreSQL extension is not loaded", "pg_connect");
}
// Prepare+execute works only in PHP 5.1+.
$this->DbSimple_Postgresql_USE_NATIVE_PHOLDERS = function_exists('pg_prepare');
$ok = $this->link = @pg_connect(
$t = (!empty($p['host']) ? 'host='.$p['host'].' ' : '').
(!empty($p['port']) ? 'port='.$p['port'].' ' : '').
'dbname='.preg_replace('{^/}s', '', $p['path']).' '.
(!empty($p['user']) ? 'user='.$p['user'].' ' : '').
(!empty($p['pass']) ? 'password='.$p['pass'].' ' : '')
);
$this->_resetLastError();
if (!$ok) return $this->_setDbError('pg_connect()');
}
function _performEscape($s, $isIdent=false)
{
if (!$isIdent)
return "'" . str_replace("'", "''", $s) . "'";
else
return '"' . str_replace('"', '_', $s) . '"';
}
function _performTransaction($parameters=null)
{
return $this->query('BEGIN');
}
function& _performNewBlob($blobid=null)
{
$obj =& new DbSimple_Postgresql_Blob($this, $blobid);
return $obj;
}
function _performGetBlobFieldNames($result)
{
$blobFields = array();
for ($i=pg_num_fields($result)-1; $i>=0; $i--) {
$type = pg_field_type($result, $i);
if (strpos($type, "BLOB") !== false) $blobFields[] = pg_field_name($result, $i);
}
return $blobFields;
}
// TODO: Real PostgreSQL escape
function _performGetPlaceholderIgnoreRe()
{
return '
" (?> [^"\\\\]+|\\\\"|\\\\)* " |
\' (?> [^\'\\\\]+|\\\\\'|\\\\)* \' |
/\* .*? \*/ # comments
';
}
function _performGetNativePlaceholderMarker($n)
{
// PostgreSQL uses specific placeholders such as $1, $2, etc.
return '$' . ($n + 1);
}
function _performCommit()
{
return $this->query('COMMIT');
}
function _performRollback()
{
return $this->query('ROLLBACK');
}
function _performTransformQuery(&$queryMain, $how)
{
// If we also need to calculate total number of found rows...
switch ($how) {
// Prepare total calculation (if possible)
case 'CALC_TOTAL':
// Not possible
return true;
// Perform total calculation.
case 'GET_TOTAL':
// TODO: GROUP BY ... -> COUNT(DISTINCT ...)
$re = '/^
(?> -- [^\r\n]* | \s+)*
(\s* SELECT \s+) #1
(.*?) #2
(\s+ FROM \s+ .*?) #3
((?:\s+ ORDER \s+ BY \s+ .*?)?) #4
((?:\s+ LIMIT \s+ \S+ \s* (?:, OFFSET \s* \S+ \s*)? )?) #5
$/six';
$m = null;
if (preg_match($re, $queryMain[0], $m)) {
$queryMain[0] = $m[1] . $this->_fieldList2Count($m[2]) . " AS C" . $m[3];
$skipTail = substr_count($m[4] . $m[5], '?');
if ($skipTail) array_splice($queryMain, -$skipTail);
}
return true;
}
return false;
}
function _performQuery($queryMain)
{
$this->_lastQuery = $queryMain;
$isInsert = preg_match('/^\s* INSERT \s+/six', $queryMain[0]);
//
// Note that in case of INSERT query we CANNOT work with prepare...execute
// cache, because RULEs do not work after pg_execute(). This is a very strange
// bug... To reproduce:
// $DB->query("CREATE TABLE test(id SERIAL, str VARCHAR(10)) WITH OIDS");
// $DB->query("CREATE RULE test_r AS ON INSERT TO test DO (SELECT 111 AS id)");
// print_r($DB->query("INSERT INTO test(str) VALUES ('test')"));
// In case INSERT + pg_execute() it returns new row OID (numeric) instead
// of result of RULE query. Strange, very strange...
//
if ($this->DbSimple_Postgresql_USE_NATIVE_PHOLDERS && !$isInsert) {
// Use native placeholders only if PG supports them.
$this->_expandPlaceholders($queryMain, true);
$hash = md5($queryMain[0]);
if (!isset($this->prepareCache[$hash])) {
$this->prepareCache[$hash] = true;
$prepared = @pg_prepare($this->link, $hash, $queryMain[0]);
if ($prepared === false) return $this->_setDbError($queryMain[0]);
} else {
// Prepare cache hit!
}
$result = pg_execute($this->link, $hash, array_slice($queryMain, 1));
} else {
// No support for native placeholders or INSERT query.
$this->_expandPlaceholders($queryMain, false);
$result = @pg_query($this->link, $queryMain[0]);
}
if ($result === false) return $this->_setDbError($queryMain);
if (!pg_num_fields($result)) {
if ($isInsert) {
// INSERT queries return generated OID (if table is WITH OIDs).
//
// Please note that unfortunately we cannot use lastval() PostgreSQL
// stored function because it generates fatal error if INSERT query
// does not contain sequence-based field at all. This error terminates
// the current transaction, and we cannot continue to work nor know
// if table contains sequence-updateable field or not.
//
// To use auto-increment functionality you must invoke
// $insertedId = $DB->query("SELECT lastval()")
// manually where it is really needed.
//
return @pg_last_oid($result);
}
// Non-SELECT queries return number of affected rows, SELECT - resource.
return @pg_affected_rows($result);
}
return $result;
}
function _performFetch($result)
{
$row = @pg_fetch_assoc($result);
if (pg_last_error($this->link)) return $this->_setDbError($this->_lastQuery);
if ($row === false) return null;
return $row;
}
function _setDbError($query)
{
return $this->_setLastError(null, pg_last_error($this->link), $query);
}
function _getVersion()
{
}
}
class DbSimple_Postgresql_Blob extends DbSimple_Generic_Blob
{
var $blob; // resourse link
var $id;
var $database;
function DbSimple_Postgresql_Blob(&$database, $id=null)
{
$this->database =& $database;
$this->database->transaction();
$this->id = $id;
$this->blob = null;
}
function read($len)
{
if ($this->id === false) return ''; // wr-only blob
if (!($e=$this->_firstUse())) return $e;
$data = @pg_lo_read($this->blob, $len);
if ($data === false) return $this->_setDbError('read');
return $data;
}
function write($data)
{
if (!($e=$this->_firstUse())) return $e;
$ok = @pg_lo_write($this->blob, $data);
if ($ok === false) return $this->_setDbError('add data to');
return true;
}
function close()
{
if (!($e=$this->_firstUse())) return $e;
if ($this->blob) {
$id = @pg_lo_close($this->blob);
if ($id === false) return $this->_setDbError('close');
$this->blob = null;
} else {
$id = null;
}
$this->database->commit();
return $this->id? $this->id : $id;
}
function length()
{
if (!($e=$this->_firstUse())) return $e;
@pg_lo_seek($this->blob, 0, PGSQL_SEEK_END);
$len = @pg_lo_tell($this->blob);
@pg_lo_seek($this->blob, 0, PGSQL_SEEK_SET);
if (!$len) return $this->_setDbError('get length of');
return $len;
}
function _setDbError($query)
{
$hId = $this->id === null? "null" : ($this->id === false? "false" : $this->id);
$query = "-- $query BLOB $hId";
$this->database->_setDbError($query);
}
// Called on each blob use (reading or writing).
function _firstUse()
{
// BLOB opened - do nothing.
if (is_resource($this->blob)) return true;
// Open or create blob.
if ($this->id !== null) {
$this->blob = @pg_lo_open($this->database->link, $this->id, 'rw');
if ($this->blob === false) return $this->_setDbError('open');
} else {
$this->id = @pg_lo_create($this->database->link);
$this->blob = @pg_lo_open($this->database->link, $this->id, 'w');
if ($this->blob === false) return $this->_setDbError('create');
}
return true;
}
}
?>
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