<?php
/* For licensing terms, see /license.txt */
/**
* This is a special version of the main database library for Chamilo focused
* on using the MySQLi driver instead of the MySQL driver.
* To use it, make a backup copy of your database.lib.php file and replace
* database.lib.php by this file.
* Include/require it in your code to use its functionality.
* Because this library contains all the basic database calls, it could be
* replaced by another library for say, PostgreSQL, to actually use Chamilo
* with another database (this is not ready yet because a lot of code still
* uses the MySQL database functions extensively).
*
* @package chamilo.library
*/
/* Loading constants */
require_once 'database.constants.inc.php';
/**
* DATABASE CLASS
* The class and its methods
* @package chamilo.library
*/
class Database {
/*
Accessor methods
Usually, you won't need these directly but instead
rely on of the get_xxx_table methods.
*/
/**
* Returns the name of the main database.
*/
public static function get_main_database() {
global $_configuration;
return $_configuration['main_database'];
}
/**
* Returns the name of the statistics database.
*/
public static function get_statistic_database() {
global $_configuration;
return $_configuration['statistics_database'];
}
/**
* Returns the name of the SCORM database.
* @deprecated
*/
public static function get_scorm_database() {
global $_configuration;
return $_configuration['scorm_database'];
}
/**
* Returns the name of the database where all the personal stuff of the user is stored
*/
public static function get_user_personal_database() {
global $_configuration;
return $_configuration['user_personal_database'];
}
/**
* Returns the name of the current course database.
* @return mixed Glued database name of false if undefined
*/
public static function get_current_course_database() {
$course_info = api_get_course_info();
if (empty($course_info['dbName'])) {
return false;
}
return $course_info['dbName'];
}
/**
* Returns the glued name of the current course database.
* @return mixed Glued database name of false if undefined
*/
public static function get_current_course_glued_database() {
$course_info = api_get_course_info();
if (empty($course_info['dbNameGlu'])) {
return false;
}
return $course_info['dbNameGlu'];
}
/**
* The glue is the string needed between database and table.
* The trick is: in multiple databases, this is a period (with backticks).
* In single database, this can be e.g. an underscore so we just fake
* there are multiple databases and the code can be written independent
* of the single / multiple database setting.
*/
public static function get_database_glue() {
global $_configuration;
return $_configuration['db_glue'];
}
/**
* Returns the database prefix.
* All created COURSE databases are prefixed with this string.
*
* TIP: This can be convenient e.g. if you have multiple system installations
* on the same physical server.
*/
public static function get_database_name_prefix() {
global $_configuration;
return $_configuration['db_prefix'];
}
/**
* Returns the course table prefix for single database.
* Not certain exactly when this is used.
* Do research.
* It's used in local.inc.php.
*/
public static function get_course_table_prefix() {
global $_configuration;
return $_configuration['table_prefix'];
}
/*
Table name methods
Use these methods to get table names for queries,
instead of constructing them yourself.
Backticks automatically surround the result,
e.g. `COURSE_NAME`.`link`
so the queries can look cleaner.
Example:
$table = Database::get_course_table(TABLE_DOCUMENT);
$sql_query = "SELECT * FROM $table WHERE $condition";
$sql_result = Database::query($sql_query);
$result = Database::fetch_array($sql_result);
*/
/**
* A more generic method than the other get_main_xxx_table methods,
* This one returns the correct complete name of any table of the main database of which you pass
* the short name as a parameter.
* Please, define table names as constants in this library and use them
* instead of directly using magic words in your tool code.
*
* @param string $short_table_name, the name of the table
*/
public static function get_main_table($short_table_name) {
return self::format_table_name(self::get_main_database(), $short_table_name);
}
/**
* A more generic method than the older get_course_xxx_table methods,
* This one can return the correct complete name of any course table of which you pass
* the short name as a parameter.
* Please, define table names as constants in this library and use them
* instead of directly using magic words in your tool code.
*
* @param string $short_table_name, the name of the table
* @param string $database_name, optional, name of the course database
* - if you don't specify this, you work on the current course.
*/
public static function get_course_table($short_table_name, $database_name = '') {
return self::format_glued_course_table_name(self::fix_database_parameter($database_name), $short_table_name);
}
/**
* Gets a complete course table name from a course code
*
* @param string $course_code
* @param string $table the name of the table
*/
public static function get_course_table_from_code($course_code, $table) {
$course_table = self::get_main_table(TABLE_MAIN_COURSE);
$course_cat_table = self::get_main_table(TABLE_MAIN_CATEGORY);
$result = self::fetch_array(self::query(
"SELECT $course_table.db_name, $course_cat_table.code
FROM $course_table
LEFT JOIN $course_cat_table
ON $course_table.category_code = $course_cat_table.code
WHERE $course_table.code = '$course_code'
LIMIT 1"));
return sprintf("%s.%s", $result[0], $table);
}
/**
* This generic method returns the correct and complete name of any statistic table
* of which you pass the short name as a parameter.
* Please, define table names as constants in this library and use them
* instead of directly using magic words in your tool code.
*
* @param string $short_table_name, the name of the table
*/
public static function get_statistic_table($short_table_name) {
return self::format_table_name(self::get_statistic_database(), $short_table_name);
}
/**
* This generic method returns the correct and complete name of any scorm
* table of which you pass the short name as a parameter. Please, define
* table names as constants in this library and use them instead of directly
* using magic words in your tool code.
*
* @param string $short_table_name, the name of the table
*/
public static function get_scorm_table($short_table_name) {
return self::format_table_name(self::get_scorm_database(), $short_table_name);
}
/**
* This generic method returns the correct and complete name of any scorm
* table of which you pass the short name as a parameter. Please, define
* table names as constants in this library and use them instead of directly
* using magic words in your tool code.
*
* @param string $short_table_name, the name of the table
*/
public static function get_user_personal_table($short_table_name) {
return self::format_table_name(self::get_user_personal_database(), $short_table_name);
}
public static function get_course_chat_connected_table($database_name = '') {
return self::format_glued_course_table_name(self::fix_database_parameter($database_name), CHAT_CONNECTED_TABLE);
}
/*
Query methods
These methods execute a query and return the result(s).
*/
/**
* @return a list (array) of all courses.
* @todo shouldn't this be in the course.lib.php script?
*/
public static function get_course_list() {
$table = self::get_main_table(TABLE_MAIN_COURSE);
return self::store_result(self::query("SELECT * FROM $table"));
}
/**
* Returns an array with all database fields for the specified course.
*
* @param the real (system) code of the course (ID from inside the main course table)
* @todo shouldn't this be in the course.lib.php script?
*/
public static function get_course_info($course_code) {
$course_code = self::escape_string($course_code);
$table = self::get_main_table(TABLE_MAIN_COURSE);
$result = self::generate_abstract_course_field_names(
self::fetch_array(self::query("SELECT * FROM $table WHERE `code` = '$course_code'")));
return $result === false ? array('db_name' => '') : $result;
}
/**
* @param $user_id (integer): the id of the user
* @return $user_info (array): user_id, lastname, firstname, username, email, ...
* @author Patrick Cool < patrick.cool @ UGent . be > , expanded to get info for any user
* @author Roan Embrechts, first version + converted to Database API
* @version 30 September 2004
* @desc find all the information about a specified user. Without parameter this is the current user.
* @todo shouldn't this be in the user.lib.php script?
*/
public static function get_user_info_from_id($user_id = '') {
if (empty($user_id)) {
return $GLOBALS['_user'];
}
$table = self::get_main_table(TABLE_MAIN_USER);
$user_id = self::escape_string($user_id);
return self::generate_abstract_user_field_names(
self::fetch_array(self::query("SELECT * FROM $table WHERE user_id = '$user_id'")));
}
/**
* Returns course code from a given gradebook category's id
* @param int Category ID
* @return string Course code
* @todo move this function in a gradebook-related library
*/
public static function get_course_by_category($category_id) {
$info = self::fetch_array(self::query('SELECT course_code FROM '.self::get_main_table(TABLE_MAIN_GRADEBOOK_CATEGORY).' WHERE id='.$category_id), 'ASSOC');
return $info ? $info['course_code'] : false;
}
/**
* This method creates an abstraction layer between database field names
* and field names expected in code.
*
* This approach helps when changing database names.
* It's also useful now to get rid of the 'franglais'.
*
* @todo add more array entries to abstract course info from field names
* @author Roan Embrechts
*
* @todo What's the use of this method. I think this is better removed.
* There should be consistency in the variable names and the use throughout the scripts
* for the database name we should consistently use or db_name or database (db_name probably being the better one)
*/
public static function generate_abstract_course_field_names($result_array) {
$visual_code = isset($result_array['visual_code']) ? $result_array['visual_code'] : null;
$code = isset($result_array['code']) ? $result_array['code'] : null;
$title = isset($result_array['title']) ? $result_array['title'] : null;
$db_name = isset($result_array['db_name']) ? $result_array['db_name'] : null;
$category_code = isset($result_array['category_code']) ? $result_array['category_code'] : null;
$result_array['official_code'] = $visual_code;
$result_array['visual_code'] = $visual_code;
$result_array['real_code'] = $code;
$result_array['system_code'] = $code;
$result_array['title'] = $title;
$result_array['database'] = $db_name;
$result_array['faculty'] = $category_code;
//$result_array['directory'] = $result_array['directory'];
/*
still to do: (info taken from local.inc.php)
$_course['id' ] = $cData['cours_id' ]; //auto-assigned integer
$_course['name' ] = $cData['title' ];
$_course['official_code'] = $cData['visual_code' ]; // use in echo
$_course['sysCode' ] = $cData['code' ]; // use as key in db
$_course['path' ] = $cData['directory' ]; // use as key in path
$_course['dbName' ] = $cData['db_name' ]; // use as key in db list
$_course['dbNameGlu' ] = $_configuration['table_prefix'] . $cData['dbName'] . $_configuration['db_glue']; // use in all queries
$_course['titular' ] = $cData['tutor_name' ];
$_course['language' ] = $cData['course_language' ];
$_course['extLink' ]['url' ] = $cData['department_url' ];
$_course['extLink' ]['name'] = $cData['department_name'];
$_course['categoryCode'] = $cData['faCode' ];
$_course['categoryName'] = $cData['faName' ];
$_course['visibility' ] = (bool) ($cData['visibility'] == 2 || $cData['visibility'] == 3);
$_course['registrationAllowed'] = (bool) ($cData['visibility'] == 1 || $cData['visibility'] == 2);
*/
return $result_array;
}
/**
* This method creates an abstraction layer between database field names
* and field names expected in code.
*
* This helps when changing database names.
* It's also useful now to get rid of the 'franglais'.
*
* @todo add more array entries to abstract user info from field names
* @author Roan Embrechts
* @author Patrick Cool
*
* @todo what's the use of this function. I think this is better removed.
* There should be consistency in the variable names and the use throughout the scripts
*/
public static function generate_abstract_user_field_names($result_array) {
$result_array['firstName'] = $result_array['firstname'];
$result_array['lastName'] = $result_array['lastname'];
$result_array['mail'] = $result_array['email'];
#$result_array['picture_uri'] = $result_array['picture_uri'];
#$result_array ['user_id'] = $result_array['user_id'];
return $result_array;
}
/**
* Counts the number of rows in a table
* @param string $table The table of which the rows should be counted
* @return int The number of rows in the given table.
*/
public static function count_rows($table) {
$obj = self::fetch_object(self::query("SELECT COUNT(*) AS n FROM $table"));
return $obj->n;
}
/*
An intermediate API-layer between the system and the dabase server.
*/
/**
* Returns the number of affected rows in the last database operation.
* @param resource $connection (optional) The database server connection, for detailed description see the method query().
* @return int Returns the number of affected rows on success, and -1 if the last query failed.
*/
public static function affected_rows($connection = null) {
global $database_connection;
return $database_connection->affected_rows;
}
/**
* Closes non-persistent database connection.
* @param resource $connection (optional) The database server connection, for detailed description see the method query().
* @return bool Returns TRUE on success or FALSE on failure.
*/
public static function close($connection = null) {
return self::use_default_connection($connection) ? mysqli::close() : mysqli::close($connection);
}
/**
* Opens a connection to a database server.
* @param array $parameters (optional) An array that contains the necessary parameters for accessing the server.
* @return resource/boolean Returns a database connection on success or FALSE on failure.
* Note: Currently the array could contain MySQL-specific parameters:
* $parameters['server'], $parameters['username'], $parameters['password'],
* $parameters['new_link'], $parameters['client_flags'], $parameters['persistent'].
* For details see documentation about the functions mysql_connect() and mysql_pconnect().
* @link http://php.net/manual/en/function.mysql-connect.php
* @link http://php.net/manual/en/function.mysql-pconnect.php
*/
public static function connect($parameters = array()) {
global $database_connection;
// A MySQL-specific implementation.
if (!isset($parameters['server'])) {
$parameters['server'] = @ini_get('mysqli.default_host');
if (empty($parameters['server'])) {
$parameters['server'] = 'localhost:3306';
}
}
if (!isset($parameters['username'])) {
$parameters['username'] = @ini_get('mysqli.default_user');
}
if (!isset($parameters['password'])) {
$parameters['password'] = @ini_get('mysqli.default_pw');
}
$database_connection = $parameters['persistent']
? new mysqli('p:'.$parameters['server'], $parameters['username'], $parameters['password'])
: new mysqli($parameters['server'], $parameters['username'], $parameters['password']);
if ($database_connection->connect_errno) {
error_log($database_connection->connect_errno());
return false;
} else {
return true;
}
}
/**
* Returns the error number from the last operation done on the database server.
* @param resource $connection (optional) The database server connection, for detailed description see the method query().
* @return int Returns the error number from the last database (operation, or 0 (zero) if no error occurred.
*/
public static function errno($connection = null) {
return self::use_default_connection($connection) ? mysqli::mysqli_errno() : mysqli::mysqli_errno($connection);
}
/**
* Returns the error text from the last operation done on the database server.
* @param resource $connection (optional) The database server connection, for detailed description see the method query().
* @return string Returns the error text from the last database operation, or '' (empty string) if no error occurred.
*/
public static function error($connection = null) {
return self::use_default_connection($connection) ? mysqli::mysqli_error() : mysqli::mysqli_error($connection);
}
/**
* Escapes a string to insert into the database as text
* @param string The string to escape
* @param resource $connection (optional) The database server connection, for detailed description see the method query().
* @return string The escaped string
* @author Yannick Warnier < yannick.warnier @ dokeos . com >
* @author Patrick Cool < patrick.cool @ UGent . be > , Ghent University
*/
public static function escape_string($string, $connection = null) {
global $database_connection;
return get_magic_quotes_gpc()
? ( $database_connection->escape_string(stripslashes($string)))
: ( $database_connection->escape_string($string));
}
/**
* Gets the array from a SQL result (as returned by Database::query) - help achieving database independence
* @param resource The result from a call to sql_query (e.g. Database::query)
* @param string Optional: "ASSOC","NUM" or "BOTH", as the constant used in mysqli_fetch_array.
* @return array Array of results as returned by php
* @author Yannick Warnier < yannick.warnier @ beeznest . com >
*/
public static function fetch_array($result, $option = 'BOTH') {
return ($option == 'ASSOC') ? $result->fetch_array(MYSQLI_ASSOC) : ($option == 'NUM' ? $result->fetch_array(MYSQLI_NUM) : $result->fetch_array());
}
/**
* Gets an associative array from a SQL result (as returned by Database::query).
* This method is equivalent to calling Database::fetch_array() with 'ASSOC' value for the optional second parameter.
* @param resource $result The result from a call to sql_query (e.g. Database::query).
* @return array Returns an associative array that corresponds to the fetched row and moves the internal data pointer ahead.
*/
public static function fetch_assoc($result) {
return $result->fetch_assoc();
}
/**
* Gets the next row of the result of the SQL query (as returned by Database::query) in an object form
* @param resource The result from a call to sql_query (e.g. Database::query)
* @param string Optional class name to instanciate
* @param array Optional array of parameters
* @return object Object of class StdClass or the required class, containing the query result row
* @author Yannick Warnier < yannick.warnier @ dokeos . com >
*/
public static function fetch_object($result, $class = null, $params = null) {
return !empty($class) ? (is_array($params) ? $result->fetch_object($class, $params) : $result->fetch_object($class)) : $result->fetch_object();
}
/**
* Gets the array from a SQL result (as returned by Database::query) - help achieving database independence
* @param resource The result from a call to sql_query (see Database::query()).
* @return array Array of results as returned by php (mysql_fetch_row)
*/
public static function fetch_row($result) {
return $result->fetch_row();
}
/**
* Frees all the memory associated with the provided result identifier.
* @return bool Returns TRUE on success or FALSE on failure.
* Notes: Use this method if you are concerned about how much memory is being used for queries that return large result sets.
* Anyway, all associated result memory is automatically freed at the end of the script's execution.
*/
public static function free_result($result) {
return $result->free_result();
}
/**
* Returns the database client library version.
* @return strung Returns a string that represents the client library version.
*/
public function get_client_info() {
return mysqli_get_client_info();
}
/**
* Returns a list of databases created on the server. The list may contain all of the
* available database names or filtered database names by using a pattern.
* @param string $pattern (optional) A pattern for filtering database names as if it was needed for the SQL's LIKE clause, for example 'chamilo_%'.
* @param resource $connection (optional) The database server connection, for detailed description see the method query().
* @return array Returns in an array the retrieved list of database names.
*/
public static function get_databases($pattern = '', $connection = null) {
$result = array();
$query_result = Database::query(!empty($pattern) ? "SHOW DATABASES LIKE '".self::escape_string($pattern, $connection)."'" : "SHOW DATABASES", $connection);
while ($row = Database::fetch_row($query_result)) {
$result[] = $row[0];
}
return $result;
}
/**
* Returns a list of the fields that a given table contains. The list may contain all of the available field names or filtered field names by using a pattern.
* By using a special option, this method is able to return an indexed list of fields' properties, where field names are keys.
* @param string $table This is the examined table.
* @param string $pattern (optional) A pattern for filtering field names as if it was needed for the SQL's LIKE clause, for example 'column_%'.
* @param string $database (optional) The name of the targeted database. If it is omited, the current database is assumed, see Database::select_db().
* @param bool $including_properties (optional) When this option is true, the returned result has the followong format:
* array(field_name_1 => array(0 => property_1, 1 => property_2, ...), fieald_name_2 => array(0 => property_1, ...), ...)
* @param resource $connection (optional) The database server connection, for detailed description see the method query().
* @return array Returns in an array the retrieved list of field names.
*/
public static function get_fields($table, $pattern = '', $database = '', $including_properties = false, $connection = null) {
$result = array();
$query = "SHOW COLUMNS FROM `".self::escape_string($table, $connection)."`";
if (!empty($database)) {
$query .= " FROM `".self::escape_string($database, $connection)."`";
}
if (!empty($pattern)) {
$query .= " LIKE '".self::escape_string($pattern, $connection)."'";
}
$query_result = Database::query($query, $connection);
if ($including_properties) {
// Making an indexed list of the fields and their properties.
while ($row = Database::fetch_row($query_result)) {
$result[$row[0]] = $row;
}
} else {
// Making a plain, flat list.
while ($row = Database::fetch_row($query_result)) {
$result[] = $row[0];
}
}
return $result;
}
/**
* Returns information about the type of the current connection and the server host name.
* @param resource $connection (optional) The database server connection, for detailed description see the method query().
* @return string/boolean Returns string data on success or FALSE on failure.
*/
public function get_host_info($connection = null) {
return self::use_default_connection($connection) ? mysqli::mysqli_get_host_info() : mysqli::mysqli_get_host_info($connection);
}
/**
* Retrieves database client/server protocol version.
* @param resource $connection (optional) The database server connection, for detailed description see the method query().
* @return int/boolean Returns the protocol version on success or FALSE on failure.
*/
public function get_proto_info($connection = null) {
return self::use_default_connection($connection) ? mysqli::mysqli_get_proto_info() : mysqli::mysqli_get_proto_info($connection);
}
/**
* Retrieves the database server version.
* @param resource $connection (optional) The database server connection, for detailed description see the method query().
* @return string/boolean Returns the MySQL server version on success or FALSE on failure.
*/
public function get_server_info($connection = null) {
return self::use_default_connection($connection) ? mysqli::mysqli_get_server_info() : mysqli::mysqli_get_server_info($connection);
}
/**
* Returns a list of tables within a database. The list may contain all of the
* available table names or filtered table names by using a pattern.
* @param string $database (optional) The name of the examined database. If it is omited, the current database is assumed, see Database::select_db().
* @param string $pattern (optional) A pattern for filtering table names as if it was needed for the SQL's LIKE clause, for example 'access_%'.
* @param resource $connection (optional) The database server connection, for detailed description see the method query().
* @return array Returns in an array the retrieved list of table names.
*/
public static function get_tables($database = '', $pattern = '', $connection = null) {
$result = array();
$query = "SHOW TABLES";
if (!empty($database)) {
$query .= " FROM `".self::escape_string($database, $connection)."`";
}
if (!empty($pattern)) {
$query .= " LIKE '".self::escape_string($pattern, $connection)."'";
}
$query_result = Database::query($query, $connection);
while ($row = Database::fetch_row($query_result)) {
$result[] = $row[0];
}
return $result;
}
/**
* Gets the ID of the last item inserted into the database
* @param resource $connection (optional) The database server connection, for detailed description see the method query().
* @return int The last ID as returned by the DB function
* @comment This should be updated to use ADODB at some point
*/
public static function insert_id($connection = null) {
global $database_connection;
return $database_connection->insert_id;
}
/**
* Gets the number of rows from the last query result - help achieving database independence
* @param resource The result
* @return integer The number of rows contained in this result
* @author Yannick Warnier < yannick.warnier @ dokeos . com >
**/
public static function num_rows($result) {
return is_a($result,'mysqli_result') ? $result->num_rows : false;
}
/**
* Acts as the relative *_result() function of most DB drivers and fetches a
* specific line and a field
* @param resource The database resource to get data from
* @param integer The row number
* @param string Optional field name or number
* @result mixed One cell of the result, or FALSE on error
*/
public static function result(& $resource, $row, $field = '') {
if (self::num_rows($resource) > 0) {
if (!empty($field)) {
$r = mysqli_data_seek($resource, $row);
return $r[$field];
} else {
return mysqli_data_seek($resource, $row);
}
} else { return null; }
}
/**
* This method returns a resource
* Documentation has been added by Arthur Portugal
* Some adaptations have been implemented by Ivan Tcholakov, 2009, 2010
* @author Olivier Brouckaert
* @param string $query The SQL query
* @param resource $connection (optional) The database server (MySQL) connection.
* If it is not specified, the connection opened by mysql_connect() is assumed.
* If no connection is found, the server will try to create one as if mysql_connect() was called with no arguments.
* If no connection is found or established, an E_WARNING level error is generated.
* @param string $file (optional) On error it shows the file in which the error has been trigerred (use the "magic" constant __FILE__ as input parameter)
* @param string $line (optional) On error it shows the line in which the error has been trigerred (use the "magic" constant __LINE__ as input parameter)
* @return resource The returned result from the query
* Note: The parameter $connection could be skipped. Here are examples of this method usage:
* Database::query($query);
* $result = Database::query($query);
* Database::query($query, $connection);
* $result = Database::query($query, $connection);
* The following ways for calling this method are obsolete:
* Database::query($query, __FILE__, __LINE__);
* $result = Database::query($query, __FILE__, __LINE__);
* Database::query($query, $connection, __FILE__, __LINE__);
* $result = Database::query($query, $connection, __FILE__, __LINE__);
*/
public static function query($query, $connection = null, $file = null, $line = null) {
global $database_connection;
$result = @$database_connection->query($query);
if ($database_connection->errno) {
$backtrace = debug_backtrace(); // Retrieving information about the caller statement.
if (isset($backtrace[0])) {
$caller = & $backtrace[0];
} else {
$caller = array();
}
if (isset($backtrace[1])) {
$owner = & $backtrace[1];
} else {
$owner = array();
}
if (empty($file)) {
$file = $caller['file'];
}
if (empty($line) & & $line !== false) {
$line = $caller['line'];
}
$type = $owner['type'];
$function = $owner['function'];
$class = $owner['class'];
$server_type = api_get_setting('server_type');
if (!empty($line) & & !empty($server_type) & & $server_type != 'production') {
$info = '< pre > ' .
'< strong > DATABASE ERROR #'.self::errno($connection).':< / strong > < br / > ' .
self::remove_XSS(self::error($connection)) . '< br / > ' .
'< strong > QUERY :< / strong > < br / > ' .
self::remove_XSS($query) . '< br / > ' .
'< strong > FILE :< / strong > < br / > ' .
(empty($file) ? ' unknown ' : $file) . '< br / > ' .
'< strong > LINE :< / strong > < br / > ' .
(empty($line) ? ' unknown ' : $line) . '< br / > ';
if (empty($type)) {
if (!empty($function)) {
$info .= '< strong > FUNCTION :< / strong > < br / > ' . $function;
}
} else {
if (!empty($class) & & !empty($function)) {
$info .= '< strong > CLASS :< / strong > < br / > ' . $class . '< br / > ';
$info .= '< strong > METHOD :< / strong > < br / > ' . $function;
}
}
$info .= '< / pre > ';
echo $info;
}
}
return $result;
}
/**
* Selects a database.
* @param string $database_name The name of the database that is to be selected.
* @param resource $connection (optional) The database server connection, for detailed description see the method query().
* @return bool Returns TRUE on success or FALSE on failure.
*/
public static function select_db($database_name, $connection = null) {
global $database_connection;
$database_connection->select_db($database_name);
return !$database_connection->errno;
//return self::use_default_connection($connection) ? mysqli_select_db($connection, $database_name) : mysqli_select_db($connection, $database_name);
}
/**
* Stores a query result into an array.
*
* @author Olivier Brouckaert
* @param resource $result - the return value of the query
* @param option BOTH, ASSOC, or NUM
* @return array - the value returned by the query
*/
public static function store_result($result, $option = 'BOTH') {
$array = array();
if ($result !== false) { // For isolation from database engine's behaviour.
while ($row = self::fetch_array($result, $option)) {
$array[] = $row;
}
}
return $array;
}
/*
Encodings and collations supported by MySQL database server
*/
/**
* Checks whether a given encoding is supported by the database server.
* @param string $encoding The encoding (a system conventional id, for example 'UTF-8') to be checked.
* @return bool Returns a boolean value as a check-result.
* @author Ivan Tcholakov
*/
public static function is_encoding_supported($encoding) {
static $supported = array();
if (!isset($supported[$encoding])) {
$supported[$encoding] = false;
if (strlen($db_encoding = self::to_db_encoding($encoding)) > 0) {
if (self::num_rows(self::query("SHOW CHARACTER SET WHERE Charset = '".self::escape_string($db_encoding)."';")) > 0) {
$supported[$encoding] = true;
}
}
}
return $supported[$encoding];
}
/**
* Constructs a SQL clause about default character set and default collation for newly created databases and tables.
* Example: Database::make_charset_clause('UTF-8', 'bulgarian') returns
* DEFAULT CHARACTER SET `utf8` DEFAULT COLLATE `utf8_general_ci`
* @param string $encoding (optional) The default database/table encoding (a system conventional id) to be used.
* @param string $language (optional) Language (a system conventional id) used for choosing language sensitive collation (if it is possible).
* @return string Returns the constructed SQL clause or empty string if $encoding is not correct or is not supported.
* @author Ivan Tcholakov
*/
public static function make_charset_clause($encoding = null, $language = null) {
if (empty($encoding)) {
$encoding = api_get_system_encoding();
}
if (empty($language)) {
$language = api_get_interface_language();
}
$charset_clause = '';
if (self::is_encoding_supported($encoding)) {
$db_encoding = Database::to_db_encoding($encoding);
$charset_clause .= " DEFAULT CHARACTER SET `".$db_encoding."`";
$db_collation = Database::to_db_collation($encoding, $language);
if (!empty($db_collation)) {
$charset_clause .= " DEFAULT COLLATE `".$db_collation."`";
}
}
return $charset_clause;
}
/**
* Converts an encoding identificator to MySQL-specific encoding identifictor,
* i.e. 'UTF-8' --> 'utf8'.
* @param string $encoding The conventional encoding identificator.
* @return string Returns the corresponding MySQL-specific encoding identificator if any, otherwise returns NULL.
* @author Ivan Tcholakov
*/
public static function to_db_encoding($encoding) {
static $result = array();
if (!isset($result[$encoding])) {
$result[$encoding] = null;
$encoding_map = & self::get_db_encoding_map();
foreach ($encoding_map as $key => $value) {
if (api_equal_encodings($encoding, $key)) {
$result[$encoding] = $value;
break;
}
}
}
return $result[$encoding];
}
/**
* Converts a MySQL-specific encoding identifictor to conventional encoding identificator,
* i.e. 'utf8' --> 'UTF-8'.
* @param string $encoding The MySQL-specific encoding identificator.
* @return string Returns the corresponding conventional encoding identificator if any, otherwise returns NULL.
* @author Ivan Tcholakov
*/
public static function from_db_encoding($db_encoding) {
static $result = array();
if (!isset($result[$db_encoding])) {
$result[$db_encoding] = null;
$encoding_map = & self::get_db_encoding_map();
foreach ($encoding_map as $key => $value) {
if (strtolower($db_encoding) == $value) {
$result[$db_encoding] = $key;
break;
}
}
}
return $result[$db_encoding];
}
/**
* Chooses the default MySQL-specific collation from given encoding and language.
* @param string $encoding A conventional encoding id, i.e. 'UTF-8'
* @param string $language (optional) A conventional for the system language id, i.e. 'bulgarian'. If it is empty, the chosen collation is the default server value corresponding to the given encoding.
* @return string Returns a suitable default collation, for example 'utf8_general_ci', or NULL if collation was not found.
* @author Ivan Tcholakov
*/
public static function to_db_collation($encoding, $language = null) {
static $result = array();
if (!isset($result[$encoding][$language])) {
$result[$encoding][$language] = null;
if (self::is_encoding_supported($encoding)) {
$db_encoding = self::to_db_encoding($encoding);
if (!empty($language)) {
$lang = api_purify_language_id($language);
$res = self::check_db_collation($db_encoding, $lang);
if (empty($res)) {
$db_collation_map = & self::get_db_collation_map();
if (isset($db_collation_map[$lang])) {
$res = self::check_db_collation($db_encoding, $db_collation_map[$lang]);
}
}
if (empty($res)) {
$res = self::check_db_collation($db_encoding, null);
}
$result[$encoding][$language] = $res;
} else {
$result[$encoding][$language] = self::check_db_collation($db_encoding, null);
}
}
}
return $result[$encoding][$language];
}
/*
Private methods
You should not access these from outside the class
No effort is made to keep the names / results the same.
*/
/**
* Glues a course database.
* glue format from local.inc.php.
*/
private static function glue_course_database_name($database_name) {
return self::get_course_table_prefix().$database_name.self::get_database_glue();
}
/**
* @param string $database_name, can be empty to use current course db
*
* @return the glued parameter if it is not empty,
* or the current course database (glued) if the parameter is empty.
*/
private static function fix_database_parameter($database_name) {
if (empty($database_name)) {
$course_info = api_get_course_info();
return $course_info['dbNameGlu'];
}
return self::glue_course_database_name($database_name);
}
/**
* Structures a course database and table name to ready them
* for querying. The course database parameter is considered glued:
* e.g. COURSE001`.`
*/
private static function format_glued_course_table_name($database_name_with_glue, $table) {
return '`'.$database_name_with_glue.$table.'`';
}
/**
* Structures a database and table name to ready them
* for querying. The database parameter is considered not glued,
* just plain e.g. COURSE001
*/
private static function format_table_name($database, $table) {
return '`'.$database.'`.`'.$table.'`';
}
/**
* This private method is to be used by the other methods in this class for
* checking whether the input parameter $connection actually has been provided.
* If the input parameter connection is not a resource or if it is not FALSE (in case of error)
* then the default opened connection should be used by the called method.
* @param resource/boolean $connection The checked parameter $connection.
* @return boolean TRUE means that calling method should use the default connection.
* FALSE means that (valid) parameter $connection has been provided and it should be used.
*/
private static function use_default_connection($connection) {
return !is_resource($connection) & & $connection !== false;
}
/**
* This private method tackles the XSS injections. It is similar to Security::remove_XSS() and works always,
* including the time of initialization when the class Security has not been loaded yet.
* @param string The input variable to be filtered from XSS, in this class it is expected to be a string.
* @return string Returns the filtered string as a result.
*/
private static function remove_XSS(& $var) {
return class_exists('Security') ? Security::remove_XSS($var) : @htmlspecialchars($var, ENT_QUOTES, api_get_system_encoding());
}
/**
* This private method encapsulates a table with relations between
* conventional and MuSQL-specific encoding identificators.
* @author Ivan Tcholakov
*/
private static function & get_db_encoding_map() {
static $encoding_map = array(
'ARMSCII-8' => 'armscii8',
'BIG5' => 'big5',
'BINARY' => 'binary',
'CP866' => 'cp866',
'EUC-JP' => 'ujis',
'EUC-KR' => 'euckr',
'GB2312' => 'gb2312',
'GBK' => 'gbk',
'ISO-8859-1' => 'latin1',
'ISO-8859-2' => 'latin2',
'ISO-8859-7' => 'greek',
'ISO-8859-8' => 'hebrew',
'ISO-8859-9' => 'latin5',
'ISO-8859-13' => 'latin7',
'ISO-8859-15' => 'latin1',
'KOI8-R' => 'koi8r',
'KOI8-U' => 'koi8u',
'SHIFT-JIS' => 'sjis',
'TIS-620' => 'tis620',
'US-ASCII' => 'ascii',
'UTF-8' => 'utf8',
'WINDOWS-1250' => 'cp1250',
'WINDOWS-1251' => 'cp1251',
'WINDOWS-1252' => 'latin1',
'WINDOWS-1256' => 'cp1256',
'WINDOWS-1257' => 'cp1257'
);
return $encoding_map;
}
/**
* A helper language id translation table for choosing some collations.
* @author Ivan Tcholakov
*/
private static function & get_db_collation_map() {
static $db_collation_map = array(
'german' => 'german2',
'simpl_chinese' => 'chinese',
'trad_chinese' => 'chinese',
'turkce' => 'turkish'
);
return $db_collation_map;
}
/**
* Constructs a MySQL-specific collation and checks whether it is supported by the database server.
* @param string $db_encoding A MySQL-specific encoding id, i.e. 'utf8'
* @param string $language A MySQL-compatible language id, i.e. 'bulgarian'
* @return string Returns a suitable default collation, for example 'utf8_general_ci', or NULL if collation was not found.
* @author Ivan Tcholakov
*/
private static function check_db_collation($db_encoding, $language) {
if (empty($db_encoding)) {
return null;
}
if (empty($language)) {
$result = self::fetch_array(self::query("SHOW COLLATION WHERE Charset = '".self::escape_string($db_encoding)."' AND `Default` = 'Yes';"), 'NUM');
return $result ? $result[0] : null;
}
$collation = $db_encoding.'_'.$language.'_ci';
$query_result = self::query("SHOW COLLATION WHERE Charset = '".self::escape_string($db_encoding)."';");
while ($result = self::fetch_array($query_result, 'NUM')) {
if ($result[0] == $collation) {
return $collation;
}
}
return null;
}
/*
New useful DB functions
*/
/**
* Experimental useful database insert
* @todo lot of stuff to do here
*/
public static function insert($table_name, $attributes) {
if (empty($attributes) || empty($table_name)) {
return false;
}
$filtred_attributes = array();
foreach($attributes as $key => $value) {
$filtred_attributes[$key] = "'".self::escape_string($value)."'";
}
$params = array_keys($filtred_attributes); //@todo check if the field exists in the table we should use a describe of that table
$values = array_values($filtred_attributes);
if (!empty($params) & & !empty($values)) {
$sql = 'INSERT INTO '.$table_name.' ('.implode(',',$params).') VALUES ('.implode(',',$values).')';
$result = self::query($sql);
return self::get_last_insert_id();
}
return false;
}
/**
* Experimental useful database finder
* @todo lot of stuff to do here
*/
public static function select($columns = '*' , $table_name, $conditions = array(), $type_result = 'all', $option = 'ASSOC') {
$conditions = self::parse_conditions($conditions);
//@todo we could do a describe here to check the columns ...
$clean_columns = '';
if (is_array($columns)) {
$clean_columns = implode(',', $columns);
} else {
if ($columns == '*') {
$clean_columns = '*';
} else {
$clean_columns = (string)$columns;
}
}
$sql = "SELECT $clean_columns FROM $table_name $conditions";
$result = self::query($sql);
$array = array();
//if (self::num_rows($result) > 0 ) {
if ($type_result == 'all') {
while ($row = self::fetch_array($result, $option)) {
if (isset($row['id'])) {
$array[$row['id']] = $row;
} else {
$array[] = $row;
}
}
} else {
$array = self::fetch_array($result, $option);
}
return $array;
}
/**
* Parses WHERE/ORDER conditions i.e array('where'=>array('id = ?' =>'4'), 'order'=>'id DESC'))
* @param array
* @todo lot of stuff to do here
*/
private function parse_conditions($conditions) {
if (empty($conditions)) {
return '';
}
$return_value = '';
foreach ($conditions as $type_condition => $condition_data) {
$type_condition = strtolower($type_condition);
switch($type_condition) {
case 'where':
foreach ($condition_data as $condition => $value_array) {
if (is_array($value_array)) {
$clean_values = array();
foreach($value_array as $item) {
$item = Database::escape_string($item);
$clean_values[]= $item;
}
} else {
$value_array = Database::escape_string($value_array);
$clean_values = $value_array;
}
if (!empty($condition) & & $clean_values != '') {
$condition = str_replace('%',"'@percentage@'", $condition); //replace "%"
$condition = str_replace("'?'","%s", $condition);
$condition = str_replace("?","%s", $condition);
$condition = str_replace("@%s@","@-@", $condition);
$condition = str_replace("%s","'%s'", $condition);
$condition = str_replace("@-@","@%s@", $condition);
//Treat conditons as string
$condition = vsprintf($condition, $clean_values);
$condition = str_replace('@percentage@','%', $condition); //replace "%"
$where_return .= $condition;
}
}
if (!empty($where_return)) {
$return_value = " WHERE $where_return" ;
}
break;
case 'order':
$order_array = $condition_data;
if (!empty($order_array)) {
// 'order' => 'id desc, name desc'
$order_array = self::escape_string($order_array);
$new_order_array = explode(',', $order_array);
$temp_value = array();
foreach($new_order_array as $element) {
$element = explode(' ', $element);
$element = array_filter($element);
$element = array_values($element);
if (!empty($element[1])) {
$element[1] = strtolower($element[1]);
$order = 'DESC';
if (in_array($element[1], array('desc', 'asc'))) {
$order = $element[1];
}
$temp_value[]= $element[0].' '.$order.' ';
} else {
//by default DESC
$temp_value[]= $element[0].' DESC ';
}
}
if (!empty($temp_value)) {
$return_value .= ' ORDER BY '.implode(', ', $temp_value);
} else {
//$return_value .= '';
}
}
break;
case 'limit':
$limit_array = explode(',', $condition_data);
if (!empty($limit_array)) {
if (count($limit_array) > 1) {
$return_value .= ' LIMIT '.intval($limit_array[0]).' , '.intval($limit_array[1]);
} else {
$return_value .= ' LIMIT '.intval($limit_array[0]);
}
}
break;
}
}
return $return_value;
}
private function parse_where_conditions($coditions){
return self::parse_conditions(array('where'=>$coditions));
}
/**
* Experimental useful database update
* @todo lot of stuff to do here
*/
public static function delete($table_name, $where_conditions) {
$result = false;
$where_return = self::parse_where_conditions($where_conditions);
$sql = "DELETE FROM $table_name $where_return ";
$result = self::query($sql);
$affected_rows = self::affected_rows();
//@todo should return affected_rows for
return $affected_rows;
}
/**
* Experimental useful database update
* @todo lot of stuff to do here
*/
public static function update($table_name, $attributes, $where_conditions = array()) {
if (!empty($table_name) & & !empty($attributes)) {
$update_sql = '';
//Cleaning attributes
$count = 1;
foreach ($attributes as $key=>$value) {
$value = self::escape_string($value);
$update_sql .= "$key = '$value' ";
if ($count < count ( $ attributes ) ) {
$update_sql.=', ';
}
$count++;
}
if (!empty($update_sql)) {
//Parsing and cleaning the where conditions
$where_return = self::parse_where_conditions($where_conditions);
$sql = "UPDATE $table_name SET $update_sql $where_return ";
//echo $sql; exit;
$result = self::query($sql);
$affected_rows = self::affected_rows();
return $affected_rows;
}
}
return false;
}
/*
DEPRECATED METHODS
*/
/**
* @deprecated Use api_get_language_isocode($language) instead.
*/
public static function get_language_isocode($language) {
return api_get_language_isocode($language);
}
/**
* @deprecated Use Database::insert_id() instead.
*/
public static function get_last_insert_id() {
global $database_connection;
return $database_connection->insert_id($database_connection);
}
}
//end class Database
