<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed'); /** * CodeIgniter * * An open source application development framework for PHP 5.2.4 or newer * * NOTICE OF LICENSE * * Licensed under the Open Software License version 3.0 * * This source file is subject to the Open Software License (OSL 3.0) that is * bundled with this package in the files license.txt / license.rst. It is * also available through the world wide web at this URL: * http://opensource.org/licenses/OSL-3.0 * If you did not receive a copy of the license and are unable to obtain it * through the world wide web, please send an email to * licensing@ellislab.com so we can send you a copy immediately. * * @package CodeIgniter * @author EllisLab Dev Team * @copyright Copyright (c) 2008 - 2012, EllisLab, Inc. (http://ellislab.com/) * @license http://opensource.org/licenses/OSL-3.0 Open Software License (OSL 3.0) * @link http://codeigniter.com * @since Version 1.0 * @filesource */ /** * Database Driver Class * * This is the platform-independent base DB implementation class. * This class will not be called directly. Rather, the adapter * class for the specific database will extend and instantiate it. * * @package CodeIgniter * @subpackage Drivers * @category Database * @author EllisLab Dev Team * @link http://codeigniter.com/user_guide/database/ */ abstract class CI_DB_driver { public $dsn; public $username; public $password; public $hostname; public $database; public $dbdriver = 'mysql'; public $dbprefix = ''; public $char_set = 'utf8'; public $dbcollat = 'utf8_general_ci'; public $autoinit = TRUE; // Whether to automatically initialize the DB public $swap_pre = ''; public $port = ''; public $pconnect = FALSE; public $conn_id = FALSE; public $result_id = FALSE; public $db_debug = FALSE; public $benchmark = 0; public $query_count = 0; public $bind_marker = '?'; public $save_queries = TRUE; public $queries = array(); public $query_times = array(); public $data_cache = array(); public $trans_enabled = TRUE; public $trans_strict = TRUE; protected $_trans_depth = 0; protected $_trans_status = TRUE; // Used with transactions to determine if a rollback should occur public $cache_on = FALSE; public $cachedir = ''; public $cache_autodel = FALSE; public $CACHE; // The cache class object protected $_protect_identifiers = TRUE; protected $_reserved_identifiers = array('*'); // Identifiers that should NOT be escaped public function __construct($params) { if (is_array($params)) { foreach ($params as $key => $val) { $this->$key = $val; } } log_message('debug', 'Database Driver Class Initialized'); } // -------------------------------------------------------------------- /** * Initialize Database Settings * * @return bool */ public function initialize() { /* If an established connection is available, then there's * no need to connect and select the database. * * Depending on the database driver, conn_id can be either * boolean TRUE, a resource or an object. */ if ($this->conn_id) { return TRUE; } // ---------------------------------------------------------------- // Connect to the database and set the connection ID $this->conn_id = ($this->pconnect == FALSE) ? $this->db_connect() : $this->db_pconnect(); // No connection resource? Check if there is a failover else throw an error if ( ! $this->conn_id) { // Check if there is a failover set if ( ! empty($this->failover) && is_array($this->failover)) { // Go over all the failovers foreach ($this->failover as $failover) { // Replace the current settings with those of the failover foreach ($failover as $key => $val) { $this->$key = $val; } // Try to connect $this->conn_id = ($this->pconnect == FALSE) ? $this->db_connect() : $this->db_pconnect(); // If a connection is made break the foreach loop if ($this->conn_id) { break; } } } // We still don't have a connection? if ( ! $this->conn_id) { log_message('error', 'Unable to connect to the database'); if ($this->db_debug) { $this->display_error('db_unable_to_connect'); } return FALSE; } } // ---------------------------------------------------------------- // Select the DB... assuming a database name is specified in the config file if ($this->database !== '' && ! $this->db_select()) { log_message('error', 'Unable to select database: '.$this->database); if ($this->db_debug) { $this->display_error('db_unable_to_select', $this->database); } return FALSE; } // Now we set the character set and that's all return $this->db_set_charset($this->char_set); } // -------------------------------------------------------------------- /** * Reconnect * * Keep / reestablish the db connection if no queries have been * sent for a length of time exceeding the server's idle timeout. * * This is just a dummy method to allow drivers without such * functionality to not declare it, while others will override it. * * @return void */ public function reconnect() { } // -------------------------------------------------------------------- /** * Select database * * This is just a dummy method to allow drivers without such * functionality to not declare it, while others will override it. * * @return bool */ public function db_select() { return TRUE; } // -------------------------------------------------------------------- /** * Set client character set * * @param string * @return bool */ public function db_set_charset($charset) { if (method_exists($this, '_db_set_charset') && ! $this->_db_set_charset($charset)) { log_message('error', 'Unable to set database connection charset: '.$charset); if ($this->db_debug) { $this->display_error('db_unable_to_set_charset', $charset); } return FALSE; } return TRUE; } // -------------------------------------------------------------------- /** * The name of the platform in use (mysql, mssql, etc...) * * @return string */ public function platform() { return $this->dbdriver; } // -------------------------------------------------------------------- /** * Database version number * * Returns a string containing the version of the database being used. * Most drivers will override this method. * * @return string */ public function version() { if (isset($this->data_cache['version'])) { return $this->data_cache['version']; } if (FALSE === ($sql = $this->_version())) { return ($this->db_debug) ? $this->display_error('db_unsupported_function') : FALSE; } $query = $this->query($sql); $query = $query->row(); return $this->data_cache['version'] = $query->ver; } // -------------------------------------------------------------------- /** * Version number query string * * @return string */ protected function _version() { return 'SELECT VERSION() AS ver'; } // -------------------------------------------------------------------- /** * Execute the query * * Accepts an SQL string as input and returns a result object upon * successful execution of a "read" type query. Returns boolean TRUE * upon successful execution of a "write" type query. Returns boolean * FALSE upon failure, and if the $db_debug variable is set to TRUE * will raise an error. * * @param string An SQL query string * @param array An array of binding data * @return mixed */ public function query($sql, $binds = FALSE, $return_object = TRUE) { if ($sql == '') { log_message('error', 'Invalid query: '.$sql); return ($this->db_debug) ? $this->display_error('db_invalid_query') : FALSE; } // Verify table prefix and replace if necessary if ($this->dbprefix != '' && $this->swap_pre != '' && $this->dbprefix != $this->swap_pre) { $sql = preg_replace('/(\W)'.$this->swap_pre.'(\S+?)/', '\\1'.$this->dbprefix.'\\2', $sql); } // Compile binds if needed if ($binds !== FALSE) { $sql = $this->compile_binds($sql, $binds); } // Is query caching enabled? If the query is a "read type" // we will load the caching class and return the previously // cached query if it exists if ($this->cache_on == TRUE && stripos($sql, 'SELECT') !== FALSE && $this->_cache_init()) { $this->load_rdriver(); if (FALSE !== ($cache = $this->CACHE->read($sql))) { return $cache; } } // Save the query for debugging if ($this->save_queries == TRUE) { $this->queries[] = $sql; } // Start the Query Timer $time_start = list($sm, $ss) = explode(' ', microtime()); // Run the Query if (FALSE === ($this->result_id = $this->simple_query($sql))) { if ($this->save_queries == TRUE) { $this->query_times[] = 0; } // This will trigger a rollback if transactions are being used $this->_trans_status = FALSE; // Grab the error now, as we might run some additional queries before displaying the error $error = $this->error(); // Log errors log_message('error', 'Query error: '.$error['message']); if ($this->db_debug) { // We call this function in order to roll-back queries // if transactions are enabled. If we don't call this here // the error message will trigger an exit, causing the // transactions to remain in limbo. $this->trans_complete(); // Display errors return $this->display_error(array('Error Number: '.$error['code'], $error['message'], $sql)); } return FALSE; } // Stop and aggregate the query time results $time_end = list($em, $es) = explode(' ', microtime()); $this->benchmark += ($em + $es) - ($sm + $ss); if ($this->save_queries == TRUE) { $this->query_times[] = ($em + $es) - ($sm + $ss); } // Increment the query counter $this->query_count++; // Was the query a "write" type? // If so we'll simply return true if ($this->is_write_type($sql) === TRUE) { // If caching is enabled we'll auto-cleanup any // existing files related to this particular URI if ($this->cache_on == TRUE && $this->cache_autodel == TRUE && $this->_cache_init()) { $this->CACHE->delete(); } return TRUE; } // Return TRUE if we don't need to create a result object // Currently only the Oracle driver uses this when stored // procedures are used if ($return_object !== TRUE) { return TRUE; } // Load and instantiate the result driver $driver = $this->load_rdriver(); $RES = new $driver($this); // Is query caching enabled? If so, we'll serialize the // result object and save it to a cache file. if ($this->cache_on == TRUE && $this->_cache_init()) { // We'll create a new instance of the result object // only without the platform specific driver since // we can't use it with cached data (the query result // resource ID won't be any good once we've cached the // result object, so we'll have to compile the data // and save it) $CR = new CI_DB_result(); $CR->result_object = $RES->result_object(); $CR->result_array = $RES->result_array(); $CR->num_rows = $RES->num_rows(); // Reset these since cached objects can not utilize resource IDs. $CR->conn_id = NULL; $CR->result_id = NULL; $this->CACHE->write($sql, $CR); } return $RES; } // -------------------------------------------------------------------- /** * Load the result drivers * * @return string the name of the result class */ public function load_rdriver() { $driver = 'CI_DB_'.$this->dbdriver.'_result'; if ( ! class_exists($driver)) { include_once(BASEPATH.'database/DB_result.php'); include_once(BASEPATH.'database/drivers/'.$this->dbdriver.'/'.$this->dbdriver.'_result.php'); } return $driver; } // -------------------------------------------------------------------- /** * Simple Query * This is a simplified version of the query() function. Internally * we only use it when running transaction commands since they do * not require all the features of the main query() function. * * @param string the sql query * @return mixed */ public function simple_query($sql) { if ( ! $this->conn_id) { $this->initialize(); } return $this->_execute($sql); } // -------------------------------------------------------------------- /** * Disable Transactions * This permits transactions to be disabled at run-time. * * @return void */ public function trans_off() { $this->trans_enabled = FALSE; } // -------------------------------------------------------------------- /** * Enable/disable Transaction Strict Mode * When strict mode is enabled, if you are running multiple groups of * transactions, if one group fails all groups will be rolled back. * If strict mode is disabled, each group is treated autonomously, meaning * a failure of one group will not affect any others * * @return void */ public function trans_strict($mode = TRUE) { $this->trans_strict = is_bool($mode) ? $mode : TRUE; } // -------------------------------------------------------------------- /** * Start Transaction * * @return void */ public function trans_start($test_mode = FALSE) { if ( ! $this->trans_enabled) { return FALSE; } // When transactions are nested we only begin/commit/rollback the outermost ones if ($this->_trans_depth > 0) { $this->_trans_depth += 1; return; } $this->trans_begin($test_mode); $this->_trans_depth += 1; } // -------------------------------------------------------------------- /** * Complete Transaction * * @return bool */ public function trans_complete() { if ( ! $this->trans_enabled) { return FALSE; } // When transactions are nested we only begin/commit/rollback the outermost ones if ($this->_trans_depth > 1) { $this->_trans_depth -= 1; return TRUE; } else { $this->_trans_depth = 0; } // The query() function will set this flag to FALSE in the event that a query failed if ($this->_trans_status === FALSE) { $this->trans_rollback(); // If we are NOT running in strict mode, we will reset // the _trans_status flag so that subsequent groups of transactions // will be permitted. if ($this->trans_strict === FALSE) { $this->_trans_status = TRUE; } log_message('debug', 'DB Transaction Failure'); return FALSE; } $this->trans_commit(); return TRUE; } // -------------------------------------------------------------------- /** * Lets you retrieve the transaction flag to determine if it has failed * * @return bool */ public function trans_status() { return $this->_trans_status; } // -------------------------------------------------------------------- /** * Compile Bindings * * @param string the sql statement * @param array an array of bind data * @return string */ public function compile_binds($sql, $binds) { if (strpos($sql, $this->bind_marker) === FALSE) { return $sql; } if ( ! is_array($binds)) { $binds = array($binds); } // Get the sql segments around the bind markers $segments = explode($this->bind_marker, $sql); // The count of bind should be 1 less then the count of segments // If there are more bind arguments trim it down if (count($binds) >= count($segments)) { $binds = array_slice($binds, 0, count($segments)-1); } // Construct the binded query $result = $segments[0]; $i = 0; foreach ($binds as $bind) { $result .= $this->escape($bind).$segments[++$i]; } return $result; } // -------------------------------------------------------------------- /** * Determines if a query is a "write" type. * * @param string An SQL query string * @return bool */ public function is_write_type($sql) { return (bool) preg_match('/^\s*"?(SET|INSERT|UPDATE|DELETE|REPLACE|CREATE|DROP|TRUNCATE|LOAD DATA|COPY|ALTER|RENAME|GRANT|REVOKE|LOCK|UNLOCK|OPTIMIZE|REINDEX)\s+/i', $sql); } // -------------------------------------------------------------------- /** * Calculate the aggregate query elapsed time * * @param int The number of decimal places * @return int */ public function elapsed_time($decimals = 6) { return number_format($this->benchmark, $decimals); } // -------------------------------------------------------------------- /** * Returns the total number of queries * * @return int */ public function total_queries() { return $this->query_count; } // -------------------------------------------------------------------- /** * Returns the last query that was executed * * @return string */ public function last_query() { return end($this->queries); } // -------------------------------------------------------------------- /** * "Smart" Escape String * * Escapes data based on type * Sets boolean and null types * * @param string * @return mixed */ public function escape($str) { if (is_string($str) OR method_exists($str, '__toString')) { return "'".$this->escape_str($str)."'"; } elseif (is_bool($str)) { return ($str === FALSE) ? 0 : 1; } elseif (is_null($str)) { return 'NULL'; } return $str; } // -------------------------------------------------------------------- /** * Escape LIKE String * * Calls the individual driver for platform * specific escaping for LIKE conditions * * @param string * @return mixed */ public function escape_like_str($str) { return $this->escape_str($str, TRUE); } // -------------------------------------------------------------------- /** * Primary * * Retrieves the primary key. It assumes that the row in the first * position is the primary key * * @param string the table name * @return string */ public function primary($table = '') { $fields = $this->list_fields($table); return is_array($fields) ? current($fields) : FALSE; } // -------------------------------------------------------------------- /** * Returns an array of table names * * @return array */ public function list_tables($constrain_by_prefix = FALSE) { // Is there a cached result? if (isset($this->data_cache['table_names'])) { return $this->data_cache['table_names']; } if (FALSE === ($sql = $this->_list_tables($constrain_by_prefix))) { return ($this->db_debug) ? $this->display_error('db_unsupported_function') : FALSE; } $this->data_cache['table_names'] = array(); $query = $this->query($sql); foreach ($query->result_array() as $row) { // Do we know from which column to get the table name? if ( ! isset($key)) { if (isset($row['table_name'])) { $key = 'table_name'; } elseif (isset($row['TABLE_NAME'])) { $key = 'TABLE_NAME'; } else { /* We have no other choice but to just get the first element's key. * Due to array_shift() accepting it's argument by reference, if * E_STRICT is on, this would trigger a warning. So we'll have to * assign it first. */ $key = array_keys($row); $key = array_shift($key); } } $this->data_cache['table_names'][] = $row[$key]; } return $this->data_cache['table_names']; } // -------------------------------------------------------------------- /** * Determine if a particular table exists * * @return bool */ public function table_exists($table_name) { return in_array($this->protect_identifiers($table_name, TRUE, FALSE, FALSE), $this->list_tables()); } // -------------------------------------------------------------------- /** * Fetch MySQL Field Names * * @param string the table name * @return array */ public function list_fields($table = '') { // Is there a cached result? if (isset($this->data_cache['field_names'][$table])) { return $this->data_cache['field_names'][$table]; } if ($table == '') { return ($this->db_debug) ? $this->display_error('db_field_param_missing') : FALSE; } if (FALSE === ($sql = $this->_list_columns($table))) { return ($this->db_debug) ? $this->display_error('db_unsupported_function') : FALSE; } $query = $this->query($sql); $this->data_cache['field_names'][$table] = array(); foreach ($query->result_array() as $row) { // Do we know from where to get the column's name? if ( ! isset($key)) { if (isset($row['column_name'])) { $key = 'column_name'; } elseif (isset($row['COLUMN_NAME'])) { $key = 'COLUMN_NAME'; } else { /* We have no other choice but to just get the first element's key. * Due to array_shift() accepting it's argument by reference, if * E_STRICT is on, this would trigger a warning. So we'll have to * assign it first. */ $key = array_keys($row); $key = array_shift($key); } } $this->data_cache['field_names'][$table][] = $row[$key]; } return $this->data_cache['field_names'][$table]; } // -------------------------------------------------------------------- /** * Determine if a particular field exists * * @param string * @param string * @return bool */ public function field_exists($field_name, $table_name) { return in_array($field_name, $this->list_fields($table_name)); } // -------------------------------------------------------------------- /** * Returns an object with field data * * @param string the table name * @return object */ public function field_data($table = '') { if ($table == '') { return ($this->db_debug) ? $this->display_error('db_field_param_missing') : FALSE; } $query = $this->query($this->_field_data($this->protect_identifiers($table, TRUE, NULL, FALSE))); return $query->field_data(); } // -------------------------------------------------------------------- /** * Generate an insert string * * @param string the table upon which the query will be performed * @param array an associative array data of key/values * @return string */ public function insert_string($table, $data) { $fields = $values = array(); foreach ($data as $key => $val) { $fields[] = $this->_escape_identifiers($key); $values[] = $this->escape($val); } return $this->_insert($this->protect_identifiers($table, TRUE, NULL, FALSE), $fields, $values); } // -------------------------------------------------------------------- /** * Generate an update string * * @param string the table upon which the query will be performed * @param array an associative array data of key/values * @param mixed the "where" statement * @return string */ public function update_string($table, $data, $where) { if ($where == '') { return FALSE; } $fields = array(); foreach ($data as $key => $val) { $fields[$this->protect_identifiers($key)] = $this->escape($val); } if ( ! is_array($where)) { $dest = array($where); } else { $dest = array(); foreach ($where as $key => $val) { $prefix = (count($dest) == 0) ? '' : ' AND '; $key = $this->protect_identifiers($key); if ($val !== '') { if ( ! $this->_has_operator($key)) { $key .= ' ='; } $val = ' '.$this->escape($val); } $dest[] = $prefix.$key.$val; } } return $this->_update($this->protect_identifiers($table, TRUE, NULL, FALSE), $fields, $dest); } // -------------------------------------------------------------------- /** * Tests whether the string has an SQL operator * * @param string * @return bool */ protected function _has_operator($str) { return (bool) preg_match('/(\s|<|>|!|=|IS NULL|IS NOT NULL)/i', trim($str)); } // -------------------------------------------------------------------- /** * Enables a native PHP function to be run, using a platform agnostic wrapper. * * @param string the function name * @param mixed any parameters needed by the function * @return mixed */ public function call_function($function) { $driver = ($this->dbdriver == 'postgre') ? 'pg_' : $this->dbdriver.'_'; if (FALSE === strpos($driver, $function)) { $function = $driver.$function; } if ( ! function_exists($function)) { return ($this->db_debug) ? $this->display_error('db_unsupported_function') : FALSE; } return (func_num_args() > 1) ? call_user_func_array($function, array_splice(func_get_args(), 1)) : call_user_func($function); } // -------------------------------------------------------------------- /** * Set Cache Directory Path * * @param string the path to the cache directory * @return void */ public function cache_set_path($path = '') { $this->cachedir = $path; } // -------------------------------------------------------------------- /** * Enable Query Caching * * @return bool cache_on value */ public function cache_on() { return $this->cache_on = TRUE; } // -------------------------------------------------------------------- /** * Disable Query Caching * * @return bool cache_on value */ public function cache_off() { return $this->cache_on = FALSE; } // -------------------------------------------------------------------- /** * Delete the cache files associated with a particular URI * * @return bool */ public function cache_delete($segment_one = '', $segment_two = '') { return ($this->_cache_init()) ? $this->CACHE->delete($segment_one, $segment_two) : FALSE; } // -------------------------------------------------------------------- /** * Delete All cache files * * @return bool */ public function cache_delete_all() { return ($this->_cache_init()) ? $this->CACHE->delete_all() : FALSE; } // -------------------------------------------------------------------- /** * Initialize the Cache Class * * @return bool */ protected function _cache_init() { if (class_exists('CI_DB_Cache')) { if (is_object($this->CACHE)) { return TRUE; } } elseif ( ! @include_once(BASEPATH.'database/DB_cache.php')) { return $this->cache_off(); } $this->CACHE = new CI_DB_Cache($this); // pass db object to support multiple db connections and returned db objects return TRUE; } // -------------------------------------------------------------------- /** * Close DB Connection * * @return void */ public function close() { if ($this->conn_id) { $this->_close($this->conn_id); $this->conn_id = FALSE; } } // -------------------------------------------------------------------- /** * Display an error message * * @param string the error message * @param string any "swap" values * @param bool whether to localize the message * @return string sends the application/error_db.php template */ public function display_error($error = '', $swap = '', $native = FALSE) { $LANG =& load_class('Lang', 'core'); $LANG->load('db'); $heading = $LANG->line('db_error_heading'); if ($native == TRUE) { $message = (array) $error; } else { $message = ( ! is_array($error)) ? array(str_replace('%s', $swap, $LANG->line($error))) : $error; } // Find the most likely culprit of the error by going through // the backtrace until the source file is no longer in the // database folder. $trace = debug_backtrace(); foreach ($trace as $call) { if (isset($call['file']) && strpos($call['file'], BASEPATH.'database') === FALSE) { // Found it - use a relative path for safety $message[] = 'Filename: '.str_replace(array(BASEPATH, APPPATH), '', $call['file']); $message[] = 'Line Number: '.$call['line']; break; } } $error =& load_class('Exceptions', 'core'); echo $error->show_error($heading, $message, 'error_db'); exit; } // -------------------------------------------------------------------- /** * Protect Identifiers * * This function is used extensively by the Active Record class, and by * a couple functions in this class. * It takes a column or table name (optionally with an alias) and inserts * the table prefix onto it. Some logic is necessary in order to deal with * column names that include the path. Consider a query like this: * * SELECT * FROM hostname.database.table.column AS c FROM hostname.database.table * * Or a query with aliasing: * * SELECT m.member_id, m.member_name FROM members AS m * * Since the column name can include up to four segments (host, DB, table, column) * or also have an alias prefix, we need to do a bit of work to figure this out and * insert the table prefix (if it exists) in the proper position, and escape only * the correct identifiers. * * @param string * @param bool * @param mixed * @param bool * @return string */ public function protect_identifiers($item, $prefix_single = FALSE, $protect_identifiers = NULL, $field_exists = TRUE) { if ( ! is_bool($protect_identifiers)) { $protect_identifiers = $this->_protect_identifiers; } if (is_array($item)) { $escaped_array = array(); foreach ($item as $k => $v) { $escaped_array[$this->protect_identifiers($k)] = $this->protect_identifiers($v); } return $escaped_array; } // Convert tabs or multiple spaces into single spaces $item = preg_replace('/[\t ]+/', ' ', $item); // If the item has an alias declaration we remove it and set it aside. // Basically we remove everything to the right of the first space if (strpos($item, ' ') !== FALSE) { $alias = strstr($item, ' '); $item = substr($item, 0, - strlen($alias)); } else { $alias = ''; } // This is basically a bug fix for queries that use MAX, MIN, etc. // If a parenthesis is found we know that we do not need to // escape the data or add a prefix. There's probably a more graceful // way to deal with this, but I'm not thinking of it -- Rick if (strpos($item, '(') !== FALSE) { return $item.$alias; } // Break the string apart if it contains periods, then insert the table prefix // in the correct location, assuming the period doesn't indicate that we're dealing // with an alias. While we're at it, we will escape the components if (strpos($item, '.') !== FALSE) { $parts = explode('.', $item); // Does the first segment of the exploded item match // one of the aliases previously identified? If so, // we have nothing more to do other than escape the item if (in_array($parts[0], $this->ar_aliased_tables)) { if ($protect_identifiers === TRUE) { foreach ($parts as $key => $val) { if ( ! in_array($val, $this->_reserved_identifiers)) { $parts[$key] = $this->_escape_identifiers($val); } } $item = implode('.', $parts); } return $item.$alias; } // Is there a table prefix defined in the config file? If not, no need to do anything if ($this->dbprefix != '') { // We now add the table prefix based on some logic. // Do we have 4 segments (hostname.database.table.column)? // If so, we add the table prefix to the column name in the 3rd segment. if (isset($parts[3])) { $i = 2; } // Do we have 3 segments (database.table.column)? // If so, we add the table prefix to the column name in 2nd position elseif (isset($parts[2])) { $i = 1; } // Do we have 2 segments (table.column)? // If so, we add the table prefix to the column name in 1st segment else { $i = 0; } // This flag is set when the supplied $item does not contain a field name. // This can happen when this function is being called from a JOIN. if ($field_exists == FALSE) { $i++; } // Verify table prefix and replace if necessary if ($this->swap_pre != '' && strpos($parts[$i], $this->swap_pre) === 0) { $parts[$i] = preg_replace('/^'.$this->swap_pre.'(\S+?)/', $this->dbprefix.'\\1', $parts[$i]); } // We only add the table prefix if it does not already exist elseif (strpos($parts[$i], $this->dbprefix) !== 0) { $parts[$i] = $this->dbprefix.$parts[$i]; } // Put the parts back together $item = implode('.', $parts); } if ($protect_identifiers === TRUE) { $item = $this->_escape_identifiers($item); } return $item.$alias; } // Is there a table prefix? If not, no need to insert it if ($this->dbprefix != '') { // Verify table prefix and replace if necessary if ($this->swap_pre != '' && strpos($item, $this->swap_pre) === 0) { $item = preg_replace('/^'.$this->swap_pre.'(\S+?)/', $this->dbprefix.'\\1', $item); } // Do we prefix an item with no segments? elseif ($prefix_single == TRUE && strpos($item, $this->dbprefix) !== 0) { $item = $this->dbprefix.$item; } } if ($protect_identifiers === TRUE && ! in_array($item, $this->_reserved_identifiers)) { $item = $this->_escape_identifiers($item); } return $item.$alias; } // -------------------------------------------------------------------- /** * Dummy method that allows Active Record class to be disabled * * This function is used extensively by every db driver. * * @return void */ protected function _reset_select() { } } /* End of file DB_driver.php */ /* Location: ./system/database/DB_driver.php */