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<?php

/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */

/**

 * The PEAR DB driver for PHP's pgsql extension

 * for interacting with PostgreSQL databases

 *

 * PHP version 5

 *

 * LICENSE: This source file is subject to version 3.0 of the PHP license

 * that is available through the world-wide-web at the following URI:

 * http://www.php.net/license/3_0.txt.  If you did not receive a copy of

 * the PHP License and are unable to obtain it through the web, please

 * send a note to license@php.net so we can mail you a copy immediately.

 *

 * @category   Database

 * @package    DB

 * @author     Rui Hirokawa <hirokawa@php.net>

 * @author     Stig Bakken <ssb@php.net>

 * @author     Daniel Convissor <danielc@php.net>

 * @copyright  1997-2007 The PHP Group

 * @license    http://www.php.net/license/3_0.txt  PHP License 3.0

 * @version    CVS: $Id$

 * @link       http://pear.php.net/package/DB

 */

/**

 * Obtain the DB_common class so it can be extended from

 */

require_once 'DB/common.php';

/**

 * The methods PEAR DB uses to interact with PHP's pgsql extension

 * for interacting with PostgreSQL databases

 *

 * These methods overload the ones declared in DB_common.

 *

 * @category   Database

 * @package    DB

 * @author     Rui Hirokawa <hirokawa@php.net>

 * @author     Stig Bakken <ssb@php.net>

 * @author     Daniel Convissor <danielc@php.net>

 * @copyright  1997-2007 The PHP Group

 * @license    http://www.php.net/license/3_0.txt  PHP License 3.0

 * @version    Release: 1.9.2

 * @link       http://pear.php.net/package/DB

 */

class DB_pgsql extends DB_common

{

    // {{{ properties

    /**

     * The DB driver type (mysql, oci8, odbc, etc.)

     * @var string

     */

    var $phptype = 'pgsql';

    /**

     * The database syntax variant to be used (db2, access, etc.), if any

     * @var string

     */

    var $dbsyntax = 'pgsql';

    /**

     * The capabilities of this DB implementation

     *

     * The 'new_link' element contains the PHP version that first provided

     * new_link support for this DBMS.  Contains false if it's unsupported.

     *

     * Meaning of the 'limit' element:

     *   + 'emulate' = emulate with fetch row by number

     *   + 'alter'   = alter the query

     *   + false     = skip rows

     *

     * @var array

     */

    var $features = array(

        'limit'         => 'alter',

        'new_link'      => '4.3.0',

        'numrows'       => true,

        'pconnect'      => true,

        'prepare'       => false,

        'ssl'           => true,

        'transactions'  => true,

    );

    /**

     * A mapping of native error codes to DB error codes

     * @var array

     */

    var $errorcode_map = array(

    );

    /**

     * The raw database connection created by PHP

     * @var resource

     */

    var $connection;

    /**

     * The DSN information for connecting to a database

     * @var array

     */

    var $dsn = array();

    /**

     * Should data manipulation queries be committed automatically?

     * @var bool

     * @access private

     */

    var $autocommit = true;

    /**

     * The quantity of transactions begun

     *

     * {@internal  While this is private, it can't actually be designated

     * private in PHP 5 because it is directly accessed in the test suite.}}

     *

     * @var integer

     * @access private

     */

    var $transaction_opcount = 0;

    /**

     * The number of rows affected by a data manipulation query

     * @var integer

     */

    var $affected = 0;

    /**

     * The current row being looked at in fetchInto()

     * @var array

     * @access private

     */

    var $row = array();

    /**

     * The number of rows in a given result set

     * @var array

     * @access private

     */

    var $_num_rows = array();

    // }}}

    // {{{ constructor

    /**

     * This constructor calls <kbd>parent::__construct()</kbd>

     *

     * @return void

     */

    function __construct()

    {

        parent::__construct();

    }

    // }}}

    // {{{ connect()

    /**

     * Connect to the database server, log in and open the database

     *

     * Don't call this method directly.  Use DB::connect() instead.

     *

     * PEAR DB's pgsql driver supports the following extra DSN options:

     *   + connect_timeout  How many seconds to wait for a connection to

     *                       be established.  Available since PEAR DB 1.7.0.

     *   + new_link         If set to true, causes subsequent calls to

     *                       connect() to return a new connection link

     *                       instead of the existing one.  WARNING: this is

     *                       not portable to other DBMS's.  Available only

     *                       if PHP is >= 4.3.0 and PEAR DB is >= 1.7.0.

     *   + options          Command line options to be sent to the server.

     *                       Available since PEAR DB 1.6.4.

     *   + service          Specifies a service name in pg_service.conf that

     *                       holds additional connection parameters.

     *                       Available since PEAR DB 1.7.0.

     *   + sslmode          How should SSL be used when connecting?  Values:

     *                       disable, allow, prefer or require.

     *                       Available since PEAR DB 1.7.0.

     *   + tty              This was used to specify where to send server

     *                       debug output.  Available since PEAR DB 1.6.4.

     *

     * Example of connecting to a new link via a socket:

     * <code>

     * require_once 'DB.php';

     *

     * $dsn = 'pgsql://user:pass@unix(/tmp)/dbname?new_link=true';

     * $options = array(

     *     'portability' => DB_PORTABILITY_ALL,

     * );

     *

     * $db = DB::connect($dsn, $options);

     * if (PEAR::isError($db)) {

     *     die($db->getMessage());

     * }

     * </code>

     *

     * @param array $dsn         the data source name

     * @param bool  $persistent  should the connection be persistent?

     *

     * @return int  DB_OK on success. A DB_Error object on failure.

     *

     * @link http://www.postgresql.org/docs/current/static/libpq.html#LIBPQ-CONNECT

     */

    function connect($dsn, $persistent = false)

    {

        if (!PEAR::loadExtension('pgsql')) {

            return $this->raiseError(DB_ERROR_EXTENSION_NOT_FOUND);

        }

        $this->dsn = $dsn;

        if ($dsn['dbsyntax']) {

            $this->dbsyntax = $dsn['dbsyntax'];

        }

        $protocol = $dsn['protocol'] ? $dsn['protocol'] : 'tcp';

        $params = array('');

        if ($protocol == 'tcp') {

            if ($dsn['hostspec']) {

                $params[0] .= 'host=' . $dsn['hostspec'];

            }

            if ($dsn['port']) {

                $params[0] .= ' port=' . $dsn['port'];

            }

        } elseif ($protocol == 'unix') {

            // Allow for pg socket in non-standard locations.

            if ($dsn['socket']) {

                $params[0] .= 'host=' . $dsn['socket'];

            }

            if ($dsn['port']) {

                $params[0] .= ' port=' . $dsn['port'];

            }

        }

        if ($dsn['database']) {

            $params[0] .= ' dbname=\'' . addslashes($dsn['database']) . '\'';

        }

        if ($dsn['username']) {

            $params[0] .= ' user=\'' . addslashes($dsn['username']) . '\'';

        }

        if ($dsn['password']) {

            $params[0] .= ' password=\'' . addslashes($dsn['password']) . '\'';

        }

        if (!empty($dsn['options'])) {

            $params[0] .= ' options=' . $dsn['options'];

        }

        if (!empty($dsn['tty'])) {

            $params[0] .= ' tty=' . $dsn['tty'];

        }

        if (!empty($dsn['connect_timeout'])) {

            $params[0] .= ' connect_timeout=' . $dsn['connect_timeout'];

        }

        if (!empty($dsn['sslmode'])) {

            $params[0] .= ' sslmode=' . $dsn['sslmode'];

        }

        if (!empty($dsn['service'])) {

            $params[0] .= ' service=' . $dsn['service'];

        }

        if (isset($dsn['new_link'])

            && ($dsn['new_link'] == 'true' || $dsn['new_link'] === true))

        {

            if (version_compare(phpversion(), '4.3.0', '>=')) {

                $params[] = PGSQL_CONNECT_FORCE_NEW;

            }

        }

        $connect_function = $persistent ? 'pg_pconnect' : 'pg_connect';

        $ini = ini_get('track_errors');

        $php_errormsg = '';

        if ($ini) {

            $this->connection = @call_user_func_array($connect_function,

                                                      $params);

        } else {

            @ini_set('track_errors', 1);

            $this->connection = @call_user_func_array($connect_function,

                                                      $params);

            @ini_set('track_errors', $ini);

        }

        if (!$this->connection) {

            return $this->raiseError(DB_ERROR_CONNECT_FAILED,

                                     null, null, null,

                                     $php_errormsg);

        }

        return DB_OK;

    }

    // }}}

    // {{{ disconnect()

    /**

     * Disconnects from the database server

     *

     * @return bool  TRUE on success, FALSE on failure

     */

    function disconnect()

    {

        $ret = @pg_close($this->connection);

        $this->connection = null;

        return $ret;

    }

    // }}}

    // {{{ simpleQuery()

    /**

     * Sends a query to the database server

     *

     * @param string  the SQL query string

     *

     * @return mixed  + a PHP result resrouce for successful SELECT queries

     *                + the DB_OK constant for other successful queries

     *                + a DB_Error object on failure

     */

    function simpleQuery($query)

    {

        $ismanip = $this->_checkManip($query);

        $this->last_query = $query;

        $query = $this->modifyQuery($query);

        if (!$this->autocommit && $ismanip) {

            if ($this->transaction_opcount == 0) {

                $result = @pg_exec($this->connection, 'begin;');

                if (!$result) {

                    return $this->pgsqlRaiseError();

                }

            }

            $this->transaction_opcount++;

        }

        $result = @pg_exec($this->connection, $query);

        if (!$result) {

            return $this->pgsqlRaiseError();

        }

        /*

         * Determine whether queries produce affected rows, result or nothing.

         *

         * This logic was introduced in version 1.1 of the file by ssb,

         * though the regex has been modified slightly since then.

         *

         * PostgreSQL commands:

         * ABORT, ALTER, BEGIN, CLOSE, CLUSTER, COMMIT, COPY,

         * CREATE, DECLARE, DELETE, DROP TABLE, EXPLAIN, FETCH,

         * GRANT, INSERT, LISTEN, LOAD, LOCK, MOVE, NOTIFY, RESET,

         * REVOKE, ROLLBACK, SELECT, SELECT INTO, SET, SHOW,

         * UNLISTEN, UPDATE, VACUUM, WITH

         */

        if ($ismanip) {

            $this->affected = @pg_affected_rows($result);

            return DB_OK;

        } elseif (preg_match('/^\s*\(*\s*(SELECT|EXPLAIN|FETCH|SHOW|WITH)\s/si',

                             $query))

        {

            $this->row[(int)$result] = 0; // reset the row counter.

            $numrows = $this->numRows($result);

            if (is_object($numrows)) {

                return $numrows;

            }

            $this->_num_rows[(int)$result] = $numrows;

            $this->affected = 0;

            return $result;

        } else {

            $this->affected = 0;

            return DB_OK;

        }

    }

    // }}}

    // {{{ nextResult()

    /**

     * Move the internal pgsql result pointer to the next available result

     *

     * @param a valid fbsql result resource

     *

     * @access public

     *

     * @return true if a result is available otherwise return false

     */

    function nextResult($result)

    {

        return false;

    }

    // }}}

    // {{{ fetchInto()

    /**

     * Places a row from the result set into the given array

     *

     * Formating of the array and the data therein are configurable.

     * See DB_result::fetchInto() for more information.

     *

     * This method is not meant to be called directly.  Use

     * DB_result::fetchInto() instead.  It can't be declared "protected"

     * because DB_result is a separate object.

     *

     * @param resource $result    the query result resource

     * @param array    $arr       the referenced array to put the data in

     * @param int      $fetchmode how the resulting array should be indexed

     * @param int      $rownum    the row number to fetch (0 = first row)

     *

     * @return mixed  DB_OK on success, NULL when the end of a result set is

     *                 reached or on failure

     *

     * @see DB_result::fetchInto()

     */

    function fetchInto($result, &$arr, $fetchmode, $rownum = null)

    {

        $result_int = (int)$result;

        $rownum = ($rownum !== null) ? $rownum : $this->row[$result_int];

        if ($rownum >= $this->_num_rows[$result_int]) {

            return null;

        }

        if ($fetchmode & DB_FETCHMODE_ASSOC) {

            $arr = @pg_fetch_array($result, $rownum, PGSQL_ASSOC);

            if ($this->options['portability'] & DB_PORTABILITY_LOWERCASE && $arr) {

                $arr = array_change_key_case($arr, CASE_LOWER);

            }

        } else {

            $arr = @pg_fetch_row($result, $rownum);

        }

        if (!$arr) {

            return null;

        }

        if ($this->options['portability'] & DB_PORTABILITY_RTRIM) {

            $this->_rtrimArrayValues($arr);

        }

        if ($this->options['portability'] & DB_PORTABILITY_NULL_TO_EMPTY) {

            $this->_convertNullArrayValuesToEmpty($arr);

        }

        $this->row[$result_int] = ++$rownum;

        return DB_OK;

    }

    // }}}

    // {{{ freeResult()

    /**

     * Deletes the result set and frees the memory occupied by the result set

     *

     * This method is not meant to be called directly.  Use

     * DB_result::free() instead.  It can't be declared "protected"

     * because DB_result is a separate object.

     *

     * @param resource $result  PHP's query result resource

     *

     * @return bool  TRUE on success, FALSE if $result is invalid

     *

     * @see DB_result::free()

     */

    function freeResult($result)

    {

        if (is_resource($result)) {

            unset($this->row[(int)$result]);

            unset($this->_num_rows[(int)$result]);

            $this->affected = 0;

            return @pg_freeresult($result);

        }

        return false;

    }

    // }}}

    // {{{ quoteBoolean()

    /**

     * Formats a boolean value for use within a query in a locale-independent

     * manner.

     *

     * @param boolean the boolean value to be quoted.

     * @return string the quoted string.

     * @see DB_common::quoteSmart()

     * @since Method available since release 1.7.8.

     */

    function quoteBoolean($boolean) {

        return $boolean ? 'TRUE' : 'FALSE';

    }

    // }}}

    // {{{ escapeSimple()

    /**

     * Escapes a string according to the current DBMS's standards

     *

     * {@internal PostgreSQL treats a backslash as an escape character,

     * so they are escaped as well.

     *

     * @param string $str  the string to be escaped

     *

     * @return string  the escaped string

     *

     * @see DB_common::quoteSmart()

     * @since Method available since Release 1.6.0

     */

    function escapeSimple($str)

    {

        if (function_exists('pg_escape_string')) {

            /* This fixes an undocumented BC break in PHP 5.2.0 which changed

             * the prototype of pg_escape_string. I'm not thrilled about having

             * to sniff the PHP version, quite frankly, but it's the only way

             * to deal with the problem. Revision 1.331.2.13.2.10 on

             * php-src/ext/pgsql/pgsql.c (PHP_5_2 branch) is to blame, for the

             * record. */

            if (version_compare(PHP_VERSION, '5.2.0', '>=')) {

                return pg_escape_string($this->connection, $str);

            } else {

                return pg_escape_string($str);

            }

        } else {

            return str_replace("'", "''", str_replace('\\', '\\\\', $str));

        }

    }

    // }}}

    // {{{ numCols()

    /**

     * Gets the number of columns in a result set

     *

     * This method is not meant to be called directly.  Use

     * DB_result::numCols() instead.  It can't be declared "protected"

     * because DB_result is a separate object.

     *

     * @param resource $result  PHP's query result resource

     *

     * @return int  the number of columns.  A DB_Error object on failure.

     *

     * @see DB_result::numCols()

     */

    function numCols($result)

    {

        $cols = @pg_numfields($result);

        if (!$cols) {

            return $this->pgsqlRaiseError();

        }

        return $cols;

    }

    // }}}

    // {{{ numRows()

    /**

     * Gets the number of rows in a result set

     *

     * This method is not meant to be called directly.  Use

     * DB_result::numRows() instead.  It can't be declared "protected"

     * because DB_result is a separate object.

     *

     * @param resource $result  PHP's query result resource

     *

     * @return int  the number of rows.  A DB_Error object on failure.

     *

     * @see DB_result::numRows()

     */

    function numRows($result)

    {

        $rows = @pg_numrows($result);

        if ($rows === null) {

            return $this->pgsqlRaiseError();

        }

        return $rows;

    }

    // }}}

    // {{{ autoCommit()

    /**

     * Enables or disables automatic commits

     *

     * @param bool $onoff  true turns it on, false turns it off

     *

     * @return int  DB_OK on success.  A DB_Error object if the driver

     *               doesn't support auto-committing transactions.

     */

    function autoCommit($onoff = false)

    {

        // XXX if $this->transaction_opcount > 0, we should probably

        // issue a warning here.

        $this->autocommit = $onoff ? true : false;

        return DB_OK;

    }

    // }}}

    // {{{ commit()

    /**

     * Commits the current transaction

     *

     * @return int  DB_OK on success.  A DB_Error object on failure.

     */

    function commit()

    {

        if ($this->transaction_opcount > 0) {

            // (disabled) hack to shut up error messages from libpq.a

            //@fclose(@fopen("php://stderr", "w"));

            $result = @pg_exec($this->connection, 'end;');

            $this->transaction_opcount = 0;

            if (!$result) {

                return $this->pgsqlRaiseError();

            }

        }

        return DB_OK;

    }

    // }}}

    // {{{ rollback()

    /**

     * Reverts the current transaction

     *

     * @return int  DB_OK on success.  A DB_Error object on failure.

     */

    function rollback()

    {

        if ($this->transaction_opcount > 0) {

            $result = @pg_exec($this->connection, 'abort;');

            $this->transaction_opcount = 0;

            if (!$result) {

                return $this->pgsqlRaiseError();

            }

        }

        return DB_OK;

    }

    // }}}

    // {{{ affectedRows()

    /**

     * Determines the number of rows affected by a data maniuplation query

     *

     * 0 is returned for queries that don't manipulate data.

     *

     * @return int  the number of rows.  A DB_Error object on failure.

     */

    function affectedRows()

    {

        return $this->affected;

    }

    // }}}

    // {{{ nextId()

    /**

     * Returns the next free id in a sequence

     *

     * @param string  $seq_name  name of the sequence

     * @param boolean $ondemand  when true, the seqence is automatically

     *                            created if it does not exist

     *

     * @return int  the next id number in the sequence.

     *               A DB_Error object on failure.

     *

     * @see DB_common::nextID(), DB_common::getSequenceName(),

     *      DB_pgsql::createSequence(), DB_pgsql::dropSequence()

     */

    function nextId($seq_name, $ondemand = true)

    {

        $seqname = $this->getSequenceName($seq_name);

        $repeat = false;

        do {

            $this->pushErrorHandling(PEAR_ERROR_RETURN);

            $result = $this->query("SELECT NEXTVAL('${seqname}')");

            $this->popErrorHandling();

            if ($ondemand && DB::isError($result) &&

                $result->getCode() == DB_ERROR_NOSUCHTABLE) {

                $repeat = true;

                $this->pushErrorHandling(PEAR_ERROR_RETURN);

                $result = $this->createSequence($seq_name);

                $this->popErrorHandling();

                if (DB::isError($result)) {

                    return $this->raiseError($result);

                }

            } else {

                $repeat = false;

            }

        } while ($repeat);

        if (DB::isError($result)) {

            return $this->raiseError($result);

        }

        $arr = $result->fetchRow(DB_FETCHMODE_ORDERED);

        $result->free();

        return $arr[0];

    }

    // }}}

    // {{{ createSequence()

    /**

     * Creates a new sequence

     *

     * @param string $seq_name  name of the new sequence

     *

     * @return int  DB_OK on success.  A DB_Error object on failure.

     *

     * @see DB_common::createSequence(), DB_common::getSequenceName(),

     *      DB_pgsql::nextID(), DB_pgsql::dropSequence()

     */

    function createSequence($seq_name)

    {

        $seqname = $this->getSequenceName($seq_name);

        $result = $this->query("CREATE SEQUENCE ${seqname}");

        return $result;

    }

    // }}}

    // {{{ dropSequence()

    /**

     * Deletes a sequence

     *

     * @param string $seq_name  name of the sequence to be deleted

     *

     * @return int  DB_OK on success.  A DB_Error object on failure.

     *

     * @see DB_common::dropSequence(), DB_common::getSequenceName(),

     *      DB_pgsql::nextID(), DB_pgsql::createSequence()

     */

    function dropSequence($seq_name)

    {

        return $this->query('DROP SEQUENCE '

                            . $this->getSequenceName($seq_name));

    }

    // }}}

    // {{{ modifyLimitQuery()

    /**

     * Adds LIMIT clauses to a query string according to current DBMS standards

     *

     * @param string $query   the query to modify

     * @param int    $from    the row to start to fetching (0 = the first row)

     * @param int    $count   the numbers of rows to fetch

     * @param mixed  $params  array, string or numeric data to be used in

     *                         execution of the statement.  Quantity of items

     *                         passed must match quantity of placeholders in

     *                         query:  meaning 1 placeholder for non-array

     *                         parameters or 1 placeholder per array element.

     *

     * @return string  the query string with LIMIT clauses added

     *

     * @access protected

     */

    function modifyLimitQuery($query, $from, $count, $params = array())

    {

        return "$query LIMIT $count OFFSET $from";

    }

    // }}}

    // {{{ pgsqlRaiseError()

    /**

     * Produces a DB_Error object regarding the current problem

     *

     * @param int $errno  if the error is being manually raised pass a

     *                     DB_ERROR* constant here.  If this isn't passed

     *                     the error information gathered from the DBMS.

     *

     * @return object  the DB_Error object

     *

     * @see DB_common::raiseError(),

     *      DB_pgsql::errorNative(), DB_pgsql::errorCode()

     */

    function pgsqlRaiseError($errno = null)

    {

        $native = $this->errorNative();

        if (!$native) {

            $native = 'Database connection has been lost.';

            $errno = DB_ERROR_CONNECT_FAILED;

        }

        if ($errno === null) {

            $errno = $this->errorCode($native);

        }

        return $this->raiseError($errno, null, null, null, $native);

    }

    // }}}

    // {{{ errorNative()

    /**

     * Gets the DBMS' native error message produced by the last query

     *

     * {@internal Error messages are used instead of error codes

     * in order to support older versions of PostgreSQL.}}

     *

     * @return string  the DBMS' error message

     */

    function errorNative()

    {

        return @pg_errormessage($this->connection);

    }

    // }}}

    // {{{ errorCode()

    /**

     * Determines PEAR::DB error code from the database's text error message.

     *

     * @param  string  $errormsg  error message returned from the database

     * @return integer  an error number from a DB error constant

     */

    function errorCode($errormsg)

    {

        static $error_regexps;

        if (!isset($error_regexps)) {

            $error_regexps = array(

                '/column .* (of relation .*)?does not exist/i'

                    => DB_ERROR_NOSUCHFIELD,

                '/(relation|sequence|table).*does not exist|class .* not found/i'

                    => DB_ERROR_NOSUCHTABLE,

                '/index .* does not exist/'

                    => DB_ERROR_NOT_FOUND,

                '/relation .* already exists/i'

                    => DB_ERROR_ALREADY_EXISTS,

                '/(divide|division) by zero$/i'

                    => DB_ERROR_DIVZERO,

                '/pg_atoi: error in .*: can\'t parse /i'

                    => DB_ERROR_INVALID_NUMBER,

                '/invalid input syntax for( type)? (integer|numeric)/i'

                    => DB_ERROR_INVALID_NUMBER,

                '/value .* is out of range for type \w*int/i'

                    => DB_ERROR_INVALID_NUMBER,

                '/integer out of range/i'

                    => DB_ERROR_INVALID_NUMBER,

                '/value too long for type character/i'

                    => DB_ERROR_INVALID,

                '/attribute .* not found|relation .* does not have attribute/i'

                    => DB_ERROR_NOSUCHFIELD,

                '/column .* specified in USING clause does not exist in (left|right) table/i'

                    => DB_ERROR_NOSUCHFIELD,

                '/parser: parse error at or near/i'

                    => DB_ERROR_SYNTAX,

                '/syntax error at/'

                    => DB_ERROR_SYNTAX,

                '/column reference .* is ambiguous/i'

                    => DB_ERROR_SYNTAX,

                '/permission denied/'

                    => DB_ERROR_ACCESS_VIOLATION,

                '/violates not-null constraint/'

                    => DB_ERROR_CONSTRAINT_NOT_NULL,

                '/violates [\w ]+ constraint/'

                    => DB_ERROR_CONSTRAINT,

                '/referential integrity violation/'

                    => DB_ERROR_CONSTRAINT,

                '/more expressions than target columns/i'

                    => DB_ERROR_VALUE_COUNT_ON_ROW,

            );

        }

        foreach ($error_regexps as $regexp => $code) {

            if (preg_match($regexp, $errormsg)) {

                return $code;

            }

        }

        // Fall back to DB_ERROR if there was no mapping.

        return DB_ERROR;

    }

    // }}}

    // {{{ tableInfo()

    /**

     * Returns information about a table or a result set

     *

     * NOTE: only supports 'table' and 'flags' if <var>$result</var>

     * is a table name.

     *

     * @param object|string  $result  DB_result object from a query or a

     *                                 string containing the name of a table.

     *                                 While this also accepts a query result

     *                                 resource identifier, this behavior is

     *                                 deprecated.

     * @param int            $mode    a valid tableInfo mode

     *

     * @return array  an associative array with the information requested.

     *                 A DB_Error object on failure.

     *

     * @see DB_common::tableInfo()

     */

    function tableInfo($result, $mode = null)

    {

        if (is_string($result)) {

            /*

             * Probably received a table name.

             * Create a result resource identifier.

             */

            $id = @pg_exec($this->connection, "SELECT * FROM $result LIMIT 0");

            $got_string = true;

        } elseif (isset($result->result)) {

            /*

             * Probably received a result object.

             * Extract the result resource identifier.

             */

            $id = $result->result;

            $got_string = false;

        } else {

            /*

             * Probably received a result resource identifier.

             * Copy it.

             * Deprecated.  Here for compatibility only.

             */

            $id = $result;

            $got_string = false;

        }

        if (!is_resource($id)) {

            return $this->pgsqlRaiseError(DB_ERROR_NEED_MORE_DATA);

        }

        if ($this->options['portability'] & DB_PORTABILITY_LOWERCASE) {

            $case_func = 'strtolower';

        } else {

            $case_func = 'strval';

        }

        $count = @pg_numfields($id);

        $res   = array();

        if ($mode) {

            $res['num_fields'] = $count;

        }

        for ($i = 0; $i < $count; $i++) {

            $res[$i] = array(

                'table' => $got_string ? $case_func($result) : '',

                'name'  => $case_func(@pg_fieldname($id, $i)),

                'type'  => @pg_fieldtype($id, $i),

                'len'   => @pg_fieldsize($id, $i),

                'flags' => $got_string

                           ? $this->_pgFieldFlags($id, $i, $result)

                           : '',

            );

            if ($mode & DB_TABLEINFO_ORDER) {

                $res['order'][$res[$i]['name']] = $i;

            }

            if ($mode & DB_TABLEINFO_ORDERTABLE) {

                $res['ordertable'][$res[$i]['table']][$res[$i]['name']] = $i;

            }

        }

        // free the result only if we were called on a table

        if ($got_string) {

            @pg_freeresult($id);

        }

        return $res;

    }

    // }}}

    // {{{ _pgFieldFlags()

    /**

     * Get a column's flags

     *

     * Supports "not_null", "default_value", "primary_key", "unique_key"

     * and "multiple_key".  The default value is passed through

     * rawurlencode() in case there are spaces in it.

     *

     * @param int $resource   the PostgreSQL result identifier

     * @param int $num_field  the field number

     *

     * @return string  the flags

     *

     * @access private

     */

    function _pgFieldFlags($resource, $num_field, $table_name)

    {

        $field_name = @pg_fieldname($resource, $num_field);

        // Check if there's a schema in $table_name and update things

        // accordingly.

        $from = 'pg_attribute f, pg_class tab, pg_type typ';

        if (strpos($table_name, '.') !== false) {

            $from .= ', pg_namespace nsp';

            list($schema, $table) = explode('.', $table_name);

            $tableWhere = "tab.relname = '$table' AND tab.relnamespace = nsp.oid AND nsp.nspname = '$schema'";

        } else {

            $tableWhere = "tab.relname = '$table_name'";

        }

        $result = @pg_exec($this->connection, "SELECT f.attnotnull, f.atthasdef

                                FROM $from

                                WHERE tab.relname = typ.typname

                                AND typ.typrelid = f.attrelid

                                AND f.attname = '$field_name'