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<?php/*** CodeIgniter** An open source application development framework for PHP** This content is released under the MIT License (MIT)** Copyright (c) 2014 - 2019, British Columbia Institute of Technology** Permission is hereby granted, free of charge, to any person obtaining a copy* of this software and associated documentation files (the "Software"), to deal* in the Software without restriction, including without limitation the rights* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell* copies of the Software, and to permit persons to whom the Software is* furnished to do so, subject to the following conditions:** The above copyright notice and this permission notice shall be included in* all copies or substantial portions of the Software.** THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN* THE SOFTWARE.** @package CodeIgniter* @author EllisLab Dev Team* @copyright Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)* @copyright Copyright (c) 2014 - 2019, British Columbia Institute of Technology (https://bcit.ca/)* @license https://opensource.org/licenses/MIT MIT License* @link https://codeigniter.com* @since Version 1.0.0* @filesource*/defined('BASEPATH') OR exit('No direct script access allowed');/*** 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 https://codeigniter.com/user_guide/database/*/abstract class CI_DB_driver {/*** Data Source Name / Connect string** @var string*/public $dsn;/*** Username** @var string*/public $username;/*** Password** @var string*/public $password;/*** Hostname** @var string*/public $hostname;/*** Database name** @var string*/public $database;/*** Database driver** @var string*/public $dbdriver = 'mysqli';/*** Sub-driver** @used-by CI_DB_pdo_driver* @var string*/public $subdriver;/*** Table prefix** @var string*/public $dbprefix = '';/*** Character set** @var string*/public $char_set = 'utf8';/*** Collation** @var string*/public $dbcollat = 'utf8_general_ci';/*** Encryption flag/data** @var mixed*/public $encrypt = FALSE;/*** Swap Prefix** @var string*/public $swap_pre = '';/*** Database port** @var int*/public $port = NULL;/*** Persistent connection flag** @var bool*/public $pconnect = FALSE;/*** Connection ID** @var object|resource*/public $conn_id = FALSE;/*** Result ID** @var object|resource*/public $result_id = FALSE;/*** Debug flag** Whether to display error messages.** @var bool*/public $db_debug = FALSE;/*** Benchmark time** @var int*/public $benchmark = 0;/*** Executed queries count** @var int*/public $query_count = 0;/*** Bind marker** Character used to identify values in a prepared statement.** @var string*/public $bind_marker = '?';/*** Save queries flag** Whether to keep an in-memory history of queries for debugging purposes.** @var bool*/public $save_queries = TRUE;/*** Queries list** @see CI_DB_driver::$save_queries* @var string[]*/public $queries = array();/*** Query times** A list of times that queries took to execute.** @var array*/public $query_times = array();/*** Data cache** An internal generic value cache.** @var array*/public $data_cache = array();/*** Transaction enabled flag** @var bool*/public $trans_enabled = TRUE;/*** Strict transaction mode flag** @var bool*/public $trans_strict = TRUE;/*** Transaction depth level** @var int*/protected $_trans_depth = 0;/*** Transaction status flag** Used with transactions to determine if a rollback should occur.** @var bool*/protected $_trans_status = TRUE;/*** Transaction failure flag** Used with transactions to determine if a transaction has failed.** @var bool*/protected $_trans_failure = FALSE;/*** Cache On flag** @var bool*/public $cache_on = FALSE;/*** Cache directory path** @var bool*/public $cachedir = '';/*** Cache auto-delete flag** @var bool*/public $cache_autodel = FALSE;/*** DB Cache object** @see CI_DB_cache* @var object*/public $CACHE;/*** Protect identifiers flag** @var bool*/protected $_protect_identifiers = TRUE;/*** List of reserved identifiers** Identifiers that must NOT be escaped.** @var string[]*/protected $_reserved_identifiers = array('*');/*** Identifier escape character** @var string*/protected $_escape_char = '"';/*** ESCAPE statement string** @var string*/protected $_like_escape_str = " ESCAPE '%s' ";/*** ESCAPE character** @var string*/protected $_like_escape_chr = '!';/*** ORDER BY random keyword** @var array*/protected $_random_keyword = array('RAND()', 'RAND(%d)');/*** COUNT string** @used-by CI_DB_driver::count_all()* @used-by CI_DB_query_builder::count_all_results()** @var string*/protected $_count_string = 'SELECT COUNT(*) AS ';// --------------------------------------------------------------------/*** Class constructor** @param array $params* @return void*/public function __construct($params){if (is_array($params)){foreach ($params as $key => $val){$this->$key = $val;}}log_message('info', 'Database Driver Class Initialized');}// --------------------------------------------------------------------/*** Initialize Database Settings** @return bool*/public function initialize(){/* If an established connection is available, then there's* no need to connect and select the database.** Depending on the database driver, conn_id can be either* boolean TRUE, a resource or an object.*/if ($this->conn_id){return TRUE;}// ----------------------------------------------------------------// Connect to the database and set the connection ID$this->conn_id = $this->db_connect($this->pconnect);// No connection resource? Check if there is a failover else throw an errorif ( ! $this->conn_id){// Check if there is a failover setif ( ! empty($this->failover) && is_array($this->failover)){// Go over all the failoversforeach ($this->failover as $failover){// Replace the current settings with those of the failoverforeach ($failover as $key => $val){$this->$key = $val;}// Try to connect$this->conn_id = $this->db_connect($this->pconnect);// If a connection is made break the foreach loopif ($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;}}// Now we set the character set and that's allreturn $this->db_set_charset($this->char_set);}// --------------------------------------------------------------------/*** DB connect** This is just a dummy method that all drivers will override.** @return mixed*/public function db_connect(){return TRUE;}// --------------------------------------------------------------------/*** Persistent database connection** @return mixed*/public function db_pconnect(){return $this->db_connect(TRUE);}// --------------------------------------------------------------------/*** Reconnect** Keep / reestablish the db connection if no queries have been* sent for a length of time exceeding the server's idle timeout.** This is just a dummy method to allow drivers without such* functionality to not declare it, while others will override it.** @return void*/public function reconnect(){}// --------------------------------------------------------------------/*** Select database** This is just a dummy method to allow drivers without such* functionality to not declare it, while others will override it.** @return bool*/public function db_select(){return TRUE;}// --------------------------------------------------------------------/*** Last error** @return array*/public function error(){return array('code' => NULL, 'message' => NULL);}// --------------------------------------------------------------------/*** Set client character set** @param string* @return bool*/public function db_set_charset($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)->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 $sql* @param array $binds = FALSE An array of binding data* @param bool $return_object = NULL* @return mixed*/public function query($sql, $binds = FALSE, $return_object = NULL){if ($sql === ''){log_message('error', 'Invalid query: '.$sql);return ($this->db_debug) ? $this->display_error('db_invalid_query') : FALSE;}elseif ( ! is_bool($return_object)){$return_object = ! $this->is_write_type($sql);}// Verify table prefix and replace if necessaryif ($this->dbprefix !== '' && $this->swap_pre !== '' && $this->dbprefix !== $this->swap_pre){$sql = preg_replace('/(\W)'.$this->swap_pre.'(\S+?)/', '\\1'.$this->dbprefix.'\\2', $sql);}// Compile binds if neededif ($binds !== FALSE){$sql = $this->compile_binds($sql, $binds);}// Is query caching enabled? If the query is a "read type"// we will load the caching class and return the previously// cached query if it existsif ($this->cache_on === TRUE && $return_object === TRUE && $this->_cache_init()){$this->load_rdriver();if (FALSE !== ($cache = $this->CACHE->read($sql))){return $cache;}}// Save the query for debuggingif ($this->save_queries === TRUE){$this->queries[] = $sql;}// Start the Query Timer$time_start = microtime(TRUE);// Run the Queryif (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 usedif ($this->_trans_depth !== 0){$this->_trans_status = FALSE;}// Grab the error now, as we might run some additional queries before displaying the error$error = $this->error();// Log errorslog_message('error', 'Query error: '.$error['message'].' - Invalid query: '.$sql);if ($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.while ($this->_trans_depth !== 0){$trans_depth = $this->_trans_depth;$this->trans_complete();if ($trans_depth === $this->_trans_depth){log_message('error', 'Database: Failure during an automated transaction commit/rollback!');break;}}// Display errorsreturn $this->display_error(array('Error Number: '.$error['code'], $error['message'], $sql));}return FALSE;}// Stop and aggregate the query time results$time_end = microtime(TRUE);$this->benchmark += $time_end - $time_start;if ($this->save_queries === TRUE){$this->query_times[] = $time_end - $time_start;}// Increment the query counter$this->query_count++;// Will we have a result object instantiated? If not - we'll simply return TRUEif ($return_object !== TRUE){// If caching is enabled we'll auto-cleanup any existing files related to this particular URIif ($this->cache_on === TRUE && $this->cache_autodel === TRUE && $this->_cache_init()){$this->CACHE->delete();}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($this);$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, FALSE)){require_once(BASEPATH.'database/DB_result.php');require_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){if ( ! $this->initialize()){return FALSE;}}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 subsequent 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** @param bool $mode = TRUE* @return void*/public function trans_strict($mode = TRUE){$this->trans_strict = is_bool($mode) ? $mode : TRUE;}// --------------------------------------------------------------------/*** Start Transaction** @param bool $test_mode = FALSE* @return bool*/public function trans_start($test_mode = FALSE){if ( ! $this->trans_enabled){return FALSE;}return $this->trans_begin($test_mode);}// --------------------------------------------------------------------/*** Complete Transaction** @return bool*/public function trans_complete(){if ( ! $this->trans_enabled){return FALSE;}// The query() function will set this flag to FALSE in the event that a query failedif ($this->_trans_status === FALSE OR $this->_trans_failure === TRUE){$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;}return $this->trans_commit();}// --------------------------------------------------------------------/*** Lets you retrieve the transaction flag to determine if it has failed** @return bool*/public function trans_status(){return $this->_trans_status;}// --------------------------------------------------------------------/*** Begin Transaction** @param bool $test_mode* @return bool*/public function trans_begin($test_mode = FALSE){if ( ! $this->trans_enabled){return FALSE;}// When transactions are nested we only begin/commit/rollback the outermost oneselseif ($this->_trans_depth > 0){$this->_trans_depth++;return TRUE;}// Reset the transaction failure flag.// If the $test_mode flag is set to TRUE transactions will be rolled back// even if the queries produce a successful result.$this->_trans_failure = ($test_mode === TRUE);if ($this->_trans_begin()){$this->_trans_status = TRUE;$this->_trans_depth++;return TRUE;}return FALSE;}// --------------------------------------------------------------------/*** Commit Transaction** @return bool*/public function trans_commit(){if ( ! $this->trans_enabled OR $this->_trans_depth === 0){return FALSE;}// When transactions are nested we only begin/commit/rollback the outermost oneselseif ($this->_trans_depth > 1 OR $this->_trans_commit()){$this->_trans_depth--;return TRUE;}return FALSE;}// --------------------------------------------------------------------/*** Rollback Transaction** @return bool*/public function trans_rollback(){if ( ! $this->trans_enabled OR $this->_trans_depth === 0){return FALSE;}// When transactions are nested we only begin/commit/rollback the outermost oneselseif ($this->_trans_depth > 1 OR $this->_trans_rollback()){$this->_trans_depth--;return TRUE;}return FALSE;}// --------------------------------------------------------------------/*** Compile Bindings** @param string the sql statement* @param array an array of bind data* @return string*/public function compile_binds($sql, $binds){if (empty($this->bind_marker) OR strpos($sql, $this->bind_marker) === FALSE){return $sql;}elseif ( ! is_array($binds)){$binds = array($binds);$bind_count = 1;}else{// Make sure we're using numeric keys$binds = array_values($binds);$bind_count = count($binds);}// We'll need the marker length later$ml = strlen($this->bind_marker);// Make sure not to replace a chunk inside a string that happens to match the bind markerif ($c = preg_match_all("/'[^']*'|\"[^\"]*\"/i", $sql, $matches)){$c = preg_match_all('/'.preg_quote($this->bind_marker, '/').'/i',str_replace($matches[0],str_replace($this->bind_marker, str_repeat(' ', $ml), $matches[0]),$sql, $c),$matches, PREG_OFFSET_CAPTURE);// Bind values' count must match the count of markers in the queryif ($bind_count !== $c){return $sql;}}elseif (($c = preg_match_all('/'.preg_quote($this->bind_marker, '/').'/i', $sql, $matches, PREG_OFFSET_CAPTURE)) !== $bind_count){return $sql;}do{$c--;$escaped_value = $this->escape($binds[$c]);if (is_array($escaped_value)){$escaped_value = '('.implode(',', $escaped_value).')';}$sql = substr_replace($sql, $escaped_value, $matches[0][$c][1], $ml);}while ($c !== 0);return $sql;}// --------------------------------------------------------------------/*** Determines if a query is a "write" type.** @param string An SQL query string* @return bool*/public function is_write_type($sql){return (bool) preg_match('/^\s*"?(SET|INSERT|UPDATE|DELETE|REPLACE|CREATE|DROP|TRUNCATE|LOAD|COPY|ALTER|RENAME|GRANT|REVOKE|LOCK|UNLOCK|REINDEX|MERGE)\s/i', $sql);}// --------------------------------------------------------------------/*** Calculate the aggregate query elapsed time** @param int The number of decimal places* @return string*/public function elapsed_time($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($str){if (is_array($str)){$str = array_map(array(&$this, 'escape'), $str);return $str;}elseif (is_string($str) OR (is_object($str) && method_exists($str, '__toString'))){return "'".$this->escape_str($str)."'";}elseif (is_bool($str)){return ($str === FALSE) ? 0 : 1;}elseif ($str === NULL){return 'NULL';}return $str;}// --------------------------------------------------------------------/*** Escape String** @param string|string[] $str Input string* @param bool $like Whether or not the string will be used in a LIKE condition* @return string*/public function escape_str($str, $like = FALSE){if (is_array($str)){foreach ($str as $key => $val){$str[$key] = $this->escape_str($val, $like);}return $str;}$str = $this->_escape_str($str);// escape LIKE condition wildcardsif ($like === TRUE){return str_replace(array($this->_like_escape_chr, '%', '_'),array($this->_like_escape_chr.$this->_like_escape_chr, $this->_like_escape_chr.'%', $this->_like_escape_chr.'_'),$str);}return $str;}// --------------------------------------------------------------------/*** Escape LIKE String** Calls the individual driver for platform* specific escaping for LIKE conditions** @param string|string[]* @return mixed*/public function escape_like_str($str){return $this->escape_str($str, TRUE);}// --------------------------------------------------------------------/*** Platform-dependent string escape** @param string* @return string*/protected function _escape_str($str){return str_replace("'", "''", remove_invisible_characters($str, FALSE));}// --------------------------------------------------------------------/*** Primary** Retrieves the primary key. It assumes that the row in the first* position is the primary key** @param string $table Table name* @return string*/public function primary($table){$fields = $this->list_fields($table);return is_array($fields) ? current($fields) : FALSE;}// --------------------------------------------------------------------/*** "Count All" query** Generates a platform-specific query string that counts all records in* the specified database** @param string* @return int*/public function count_all($table = ''){if ($table === ''){return 0;}$query = $this->query($this->_count_string.$this->escape_identifiers('numrows').' FROM '.$this->protect_identifiers($table, TRUE, NULL, FALSE));if ($query->num_rows() === 0){return 0;}$query = $query->row();$this->_reset_select();return (int) $query->numrows;}// --------------------------------------------------------------------/*** Returns an array of table names** @param string $constrain_by_prefix = FALSE* @return array*/public function list_tables($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 its 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** @param string $table_name* @return bool*/public function table_exists($table_name){return in_array($this->protect_identifiers($table_name, TRUE, FALSE, FALSE), $this->list_tables());}// --------------------------------------------------------------------/*** Fetch Field Names** @param string $table Table name* @return array*/public function list_fields($table){if (FALSE === ($sql = $this->_list_columns($table))){return ($this->db_debug) ? $this->display_error('db_unsupported_function') : FALSE;}$query = $this->query($sql);$fields = array();foreach ($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.$key = key($row);}}$fields[] = $row[$key];}return $fields;}// --------------------------------------------------------------------/*** Determine if a particular field exists** @param string* @param string* @return bool*/public function field_exists($field_name, $table_name){return in_array($field_name, $this->list_fields($table_name));}// --------------------------------------------------------------------/*** Returns an object with field data** @param string $table the table name* @return array*/public function field_data($table){$query = $this->query($this->_field_data($this->protect_identifiers($table, TRUE, NULL, FALSE)));return ($query) ? $query->field_data() : FALSE;}// --------------------------------------------------------------------/*** Escape the SQL Identifiers** This function escapes column and table names** @param mixed* @return mixed*/public function escape_identifiers($item){if ($this->_escape_char === '' OR empty($item) OR in_array($item, $this->_reserved_identifiers)){return $item;}elseif (is_array($item)){foreach ($item as $key => $value){$item[$key] = $this->escape_identifiers($value);}return $item;}// Avoid breaking functions and literal values inside querieselseif (ctype_digit($item) OR $item[0] === "'" OR ($this->_escape_char !== '"' && $item[0] === '"') OR strpos($item, '(') !== FALSE){return $item;}static $preg_ec = array();if (empty($preg_ec)){if (is_array($this->_escape_char)){$preg_ec = array(preg_quote($this->_escape_char[0], '/'),preg_quote($this->_escape_char[1], '/'),$this->_escape_char[0],$this->_escape_char[1]);}else{$preg_ec[0] = $preg_ec[1] = preg_quote($this->_escape_char, '/');$preg_ec[2] = $preg_ec[3] = $this->_escape_char;}}foreach ($this->_reserved_identifiers as $id){if (strpos($item, '.'.$id) !== FALSE){return preg_replace('/'.$preg_ec[0].'?([^'.$preg_ec[1].'\.]+)'.$preg_ec[1].'?\./i', $preg_ec[2].'$1'.$preg_ec[3].'.', $item);}}return preg_replace('/'.$preg_ec[0].'?([^'.$preg_ec[1].'\.]+)'.$preg_ec[1].'?(\.)?/i', $preg_ec[2].'$1'.$preg_ec[3].'$2', $item);}// --------------------------------------------------------------------/*** Generate an insert string** @param string the table upon which the query will be performed* @param array an associative array data of key/values* @return string*/public function insert_string($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, $values);}// --------------------------------------------------------------------/*** Insert statement** Generates a platform-specific insert string from the supplied data** @param string the table name* @param array the insert keys* @param array the insert values* @return string*/protected function _insert($table, $keys, $values){return 'INSERT INTO '.$table.' ('.implode(', ', $keys).') VALUES ('.implode(', ', $values).')';}// --------------------------------------------------------------------/*** Generate an update string** @param string the table upon which the query will be performed* @param array an associative array data of key/values* @param mixed the "where" statement* @return string*/public function update_string($table, $data, $where){if (empty($where)){return FALSE;}$this->where($where);$fields = array();foreach ($data as $key => $val){$fields[$this->protect_identifiers($key)] = $this->escape($val);}$sql = $this->_update($this->protect_identifiers($table, TRUE, NULL, FALSE), $fields);$this->_reset_write();return $sql;}// --------------------------------------------------------------------/*** Update statement** Generates a platform-specific update string from the supplied data** @param string the table name* @param array the update data* @return string*/protected function _update($table, $values){foreach ($values as $key => $val){$valstr[] = $key.' = '.$val;}return 'UPDATE '.$table.' SET '.implode(', ', $valstr).$this->_compile_wh('qb_where').$this->_compile_order_by().($this->qb_limit !== FALSE ? ' LIMIT '.$this->qb_limit : '');}// --------------------------------------------------------------------/*** Tests whether the string has an SQL operator** @param string* @return bool*/protected function _has_operator($str){return (bool) preg_match('/(<|>|!|=|\sIS NULL|\sIS NOT NULL|\sEXISTS|\sBETWEEN|\sLIKE|\sIN\s*\(|\s)/i', trim($str));}// --------------------------------------------------------------------/*** Returns the SQL string operator** @param string* @return string*/protected function _get_operator($str){static $_operators;if (empty($_operators)){$_les = ($this->_like_escape_str !== '')? '\s+'.preg_quote(trim(sprintf($this->_like_escape_str, $this->_like_escape_chr)), '/'): '';$_operators = array('\s*(?:<|>|!)?=\s*', // =, <=, >=, !='\s*<>?\s*', // <, <>'\s*>\s*', // >'\s+IS NULL', // IS NULL'\s+IS NOT NULL', // IS NOT NULL'\s+EXISTS\s*\(.*\)', // EXISTS(sql)'\s+NOT EXISTS\s*\(.*\)', // NOT EXISTS(sql)'\s+BETWEEN\s+', // BETWEEN value AND value'\s+IN\s*\(.*\)', // IN(list)'\s+NOT IN\s*\(.*\)', // NOT IN (list)'\s+LIKE\s+\S.*('.$_les.')?', // LIKE 'expr'[ ESCAPE '%s']'\s+NOT LIKE\s+\S.*('.$_les.')?' // NOT LIKE 'expr'[ ESCAPE '%s']);}return preg_match('/'.implode('|', $_operators).'/i', $str, $match)? $match[0] : FALSE;}// --------------------------------------------------------------------/*** Enables a native PHP function to be run, using a platform agnostic wrapper.** @param string $function Function name* @return mixed*/public function call_function($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_slice(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** @param string $segment_one = ''* @param string $segment_two = ''* @return bool*/public function cache_delete($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()? $this->CACHE->delete_all(): FALSE;}// --------------------------------------------------------------------/*** Initialize the Cache Class** @return bool*/protected function _cache_init(){if ( ! class_exists('CI_DB_Cache', FALSE)){require_once(BASEPATH.'database/DB_cache.php');}elseif (is_object($this->CACHE)){return TRUE;}$this->CACHE = new CI_DB_Cache($this); // pass db object to support multiple db connections and returned db objectsreturn TRUE;}// --------------------------------------------------------------------/*** Close DB Connection** @return void*/public function close(){if ($this->conn_id){$this->_close();$this->conn_id = FALSE;}}// --------------------------------------------------------------------/*** Close DB Connection** This method would be overridden by most of the drivers.** @return void*/protected function _close(){$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/views/errors/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) ? $error : array(str_replace('%s', $swap, $LANG->line($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'], $call['class'])){// We'll need this on Windows, as APPPATH and BASEPATH will always use forward slashesif (DIRECTORY_SEPARATOR !== '/'){$call['file'] = str_replace('\\', '/', $call['file']);}if (strpos($call['file'], BASEPATH.'database') === FALSE && strpos($call['class'], 'Loader') === FALSE){// Found it - use a relative path for safety$message[] = 'Filename: '.str_replace(array(APPPATH, BASEPATH), '', $call['file']);$message[] = 'Line Number: '.$call['line'];break;}}}$error =& load_class('Exceptions', 'core');echo $error->show_error($heading, $message, 'error_db');exit(8); // EXIT_DATABASE}// --------------------------------------------------------------------/*** Protect Identifiers** This function is used extensively by the Query Builder class, and by* a couple functions in this class.* It takes a column or table name (optionally with an alias) and inserts* the table prefix onto it. Some logic is necessary in order to deal with* column names that include the path. Consider a query like this:** SELECT hostname.database.table.column AS c FROM hostname.database.table** Or a query with aliasing:** SELECT m.member_id, m.member_name FROM members AS m** Since the column name can include up to four segments (host, DB, table, column)* or also have an alias prefix, we need to do a bit of work to figure this out and* insert the table prefix (if it exists) in the proper position, and escape only* the correct identifiers.** @param string* @param bool* @param mixed* @param bool* @return string*/public function protect_identifiers($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, $prefix_single, $protect_identifiers, $field_exists);}return $escaped_array;}// This is basically a bug fix for queries that use MAX, MIN, etc.// If a parenthesis is found we know that we do not need to// escape the data or add a prefix. There's probably a more graceful// way to deal with this, but I'm not thinking of it -- Rick//// Added exception for single quotes as well, we don't want to alter// literal strings. -- Narfif (strcspn($item, "()'") !== strlen($item)){return $item;}// Convert tabs or multiple spaces into single spaces$item = preg_replace('/\s+/', ' ', trim($item));// If the item has an alias declaration we remove it and set it aside.// Note: strripos() is used in order to support spaces in table namesif ($offset = strripos($item, ' AS ')){$alias = ($protect_identifiers)? substr($item, $offset, 4).$this->escape_identifiers(substr($item, $offset + 4)): substr($item, $offset);$item = substr($item, 0, $offset);}elseif ($offset = strrpos($item, ' ')){$alias = ($protect_identifiers)? ' '.$this->escape_identifiers(substr($item, $offset + 1)): substr($item, $offset);$item = substr($item, 0, $offset);}else{$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 componentsif (strpos($item, '.') !== FALSE){$parts = explode('.', $item);// Does the first segment of the exploded item match// one of the aliases previously identified? If so,// we have nothing more to do other than escape the item//// NOTE: The ! empty() condition prevents this method// from breaking when QB isn't enabled.if ( ! empty($this->qb_aliased_tables) && in_array($parts[0], $this->qb_aliased_tables)){if ($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 anythingif ($this->dbprefix !== ''){// We now add the table prefix based on some logic.// Do we have 4 segments (hostname.database.table.column)?// If so, we add the table prefix to the column name in the 3rd segment.if (isset($parts[3])){$i = 2;}// Do we have 3 segments (database.table.column)?// If so, we add the table prefix to the column name in 2nd positionelseif (isset($parts[2])){$i = 1;}// Do we have 2 segments (table.column)?// If so, we add the table prefix to the column name in 1st segmentelse{$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){$i++;}// dbprefix may've already been applied, with or without the identifier escaped$ec = '(?<ec>'.preg_quote(is_array($this->_escape_char) ? $this->_escape_char[0] : $this->_escape_char).')?';isset($ec[0]) && $ec .= '?'; // Just in case someone has disabled escaping by forcing an empty escape character// Verify table prefix and replace if necessaryif ($this->swap_pre !== '' && preg_match('#^'.$ec.preg_quote($this->swap_pre).'#', $parts[$i])){$parts[$i] = preg_replace('#^'.$ec.preg_quote($this->swap_pre).'(\S+?)#', '\\1'.$this->dbprefix.'\\2', $parts[$i]);}// We only add the table prefix if it does not already existelse{preg_match('#^'.$ec.preg_quote($this->dbprefix).'#', $parts[$i]) OR $parts[$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 itif ($this->dbprefix !== ''){// Verify table prefix and replace if necessaryif ($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 Query Builder class to be disabled* and keep count_all() working.** @return void*/protected function _reset_select(){}}