/lib/classes/persistent.php
PHP | 979 lines | 420 code | 120 blank | 439 comment | 71 complexity | 509e2a4f53692c701bb47754900ca026 MD5 | raw file
Possible License(s): Apache-2.0, LGPL-2.1, BSD-3-Clause, MIT, GPL-3.0
- <?php
- // This file is part of Moodle - http://moodle.org/
- //
- // Moodle is free software: you can redistribute it and/or modify
- // it under the terms of the GNU General Public License as published by
- // the Free Software Foundation, either version 3 of the License, or
- // (at your option) any later version.
- //
- // Moodle is distributed in the hope that it will be useful,
- // but WITHOUT ANY WARRANTY; without even the implied warranty of
- // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- // GNU General Public License for more details.
- //
- // You should have received a copy of the GNU General Public License
- // along with Moodle. If not, see <http://www.gnu.org/licenses/>.
- /**
- * Abstract class for objects saved to the DB.
- *
- * @package core
- * @copyright 2015 Damyon Wiese
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
- namespace core;
- defined('MOODLE_INTERNAL') || die();
- use coding_exception;
- use invalid_parameter_exception;
- use lang_string;
- use ReflectionMethod;
- use stdClass;
- use renderer_base;
- /**
- * Abstract class for core objects saved to the DB.
- *
- * @copyright 2015 Damyon Wiese
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
- abstract class persistent {
- /** The table name. */
- const TABLE = null;
- /** @var array The model data. */
- private $data = array();
- /** @var array The list of validation errors. */
- private $errors = array();
- /** @var boolean If the data was already validated. */
- private $validated = false;
- /**
- * Create an instance of this class.
- *
- * @param int $id If set, this is the id of an existing record, used to load the data.
- * @param stdClass $record If set will be passed to {@link self::from_record()}.
- */
- public function __construct($id = 0, stdClass $record = null) {
- global $CFG;
- if ($id > 0) {
- $this->raw_set('id', $id);
- $this->read();
- }
- if (!empty($record)) {
- $this->from_record($record);
- }
- if ($CFG->debugdeveloper) {
- $this->verify_protected_methods();
- }
- }
- /**
- * This function is used to verify that custom getters and setters are declared as protected.
- *
- * Persistent properties should always be accessed via get('property') and set('property', 'value') which
- * will call the custom getter or setter if it exists. We do not want to allow inconsistent access to the properties.
- */
- final protected function verify_protected_methods() {
- $properties = static::properties_definition();
- foreach ($properties as $property => $definition) {
- $method = 'get_' . $property;
- if (method_exists($this, $method)) {
- $reflection = new ReflectionMethod($this, $method);
- if (!$reflection->isProtected()) {
- throw new coding_exception('The method ' . get_class($this) . '::'. $method . ' should be protected.');
- }
- }
- $method = 'set_' . $property;
- if (method_exists($this, $method)) {
- $reflection = new ReflectionMethod($this, $method);
- if (!$reflection->isProtected()) {
- throw new coding_exception('The method ' . get_class($this) . '::'. $method . ' should be protected.');
- }
- }
- }
- }
- /**
- * Data setter.
- *
- * This is the main setter for all the properties. Developers can implement their own setters (set_propertyname)
- * and they will be called by this function. Custom setters should call internal_set() to finally set the value.
- * Internally this is not used {@link self::to_record()} or
- * {@link self::from_record()} because the data is not expected to be validated or changed when reading/writing
- * raw records from the DB.
- *
- * @param string $property The property name.
- * @return $this
- *
- * @throws coding_exception
- */
- final public function set($property, $value) {
- if (!static::has_property($property)) {
- throw new coding_exception('Unexpected property \'' . s($property) .'\' requested.');
- }
- $methodname = 'set_' . $property;
- if (method_exists($this, $methodname)) {
- $this->$methodname($value);
- return $this;
- }
- return $this->raw_set($property, $value);
- }
- /**
- * Data setter for multiple properties
- *
- * Internally calls {@see set} on each property
- *
- * @param array $values Array of property => value elements
- * @return $this
- */
- final public function set_many(array $values): self {
- foreach ($values as $property => $value) {
- $this->set($property, $value);
- }
- return $this;
- }
- /**
- * Data getter.
- *
- * This is the main getter for all the properties. Developers can implement their own getters (get_propertyname)
- * and they will be called by this function. Custom getters can use raw_get to get the raw value.
- * Internally this is not used by {@link self::to_record()} or
- * {@link self::from_record()} because the data is not expected to be validated or changed when reading/writing
- * raw records from the DB.
- *
- * @param string $property The property name.
- * @return mixed
- */
- final public function get($property) {
- if (!static::has_property($property)) {
- throw new coding_exception('Unexpected property \'' . s($property) .'\' requested.');
- }
- $methodname = 'get_' . $property;
- if (method_exists($this, $methodname)) {
- return $this->$methodname();
- }
- $properties = static::properties_definition();
- // If property can be NULL and value is NULL it needs to return null.
- if ($properties[$property]['null'] === NULL_ALLOWED && $this->raw_get($property) === null) {
- return null;
- }
- // Deliberately cast boolean types as such, because clean_param will cast them to integer.
- if ($properties[$property]['type'] === PARAM_BOOL) {
- return (bool)$this->raw_get($property);
- }
- return clean_param($this->raw_get($property), $properties[$property]['type']);
- }
- /**
- * Internal Data getter.
- *
- * This is the main getter for all the properties. Developers can implement their own getters
- * but they should be calling {@link self::get()} in order to retrieve the value. Essentially
- * the getters defined by the developers would only ever be used as helper methods and will not
- * be called internally at this stage. In other words, do not expect {@link self::to_record()} or
- * {@link self::from_record()} to use them.
- *
- * This is protected because it is only for raw low level access to the data fields.
- * Note this function is named raw_get and not get_raw to avoid naming clashes with a property named raw.
- *
- * @param string $property The property name.
- * @return mixed
- */
- final protected function raw_get($property) {
- if (!static::has_property($property)) {
- throw new coding_exception('Unexpected property \'' . s($property) .'\' requested.');
- }
- if (!array_key_exists($property, $this->data) && !static::is_property_required($property)) {
- $this->raw_set($property, static::get_property_default_value($property));
- }
- return isset($this->data[$property]) ? $this->data[$property] : null;
- }
- /**
- * Data setter.
- *
- * This is the main setter for all the properties. Developers can implement their own setters
- * but they should always be calling {@link self::set()} in order to set the value. Essentially
- * the setters defined by the developers are helper methods and will not be called internally
- * at this stage. In other words do not expect {@link self::to_record()} or
- * {@link self::from_record()} to use them.
- *
- * This is protected because it is only for raw low level access to the data fields.
- *
- * @param string $property The property name.
- * @param mixed $value The value.
- * @return $this
- */
- final protected function raw_set($property, $value) {
- if (!static::has_property($property)) {
- throw new coding_exception('Unexpected property \'' . s($property) .'\' requested.');
- }
- if (!array_key_exists($property, $this->data) || $this->data[$property] != $value) {
- // If the value is changing, we invalidate the model.
- $this->validated = false;
- }
- $this->data[$property] = $value;
- return $this;
- }
- /**
- * Return the custom definition of the properties of this model.
- *
- * Each property MUST be listed here.
- *
- * The result of this method is cached internally for the whole request.
- *
- * The 'default' value can be a Closure when its value may change during a single request.
- * For example if the default value is based on a $CFG property, then it should be wrapped in a closure
- * to avoid running into scenarios where the true value of $CFG is not reflected in the definition.
- * Do not abuse closures as they obviously add some overhead.
- *
- * Examples:
- *
- * array(
- * 'property_name' => array(
- * 'default' => 'Default value', // When not set, the property is considered as required.
- * 'message' => new lang_string(...), // Defaults to invalid data error message.
- * 'null' => NULL_ALLOWED, // Defaults to NULL_NOT_ALLOWED. Takes NULL_NOW_ALLOWED or NULL_ALLOWED.
- * 'type' => PARAM_TYPE, // Mandatory.
- * 'choices' => array(1, 2, 3) // An array of accepted values.
- * )
- * )
- *
- * array(
- * 'dynamic_property_name' => array(
- * 'default' => function() {
- * return $CFG->something;
- * },
- * 'type' => PARAM_INT,
- * )
- * )
- *
- * @return array Where keys are the property names.
- */
- protected static function define_properties() {
- return array();
- }
- /**
- * Get the properties definition of this model..
- *
- * @return array
- */
- final public static function properties_definition() {
- global $CFG;
- static $def = null;
- if ($def !== null) {
- return $def;
- }
- $def = static::define_properties();
- $def['id'] = array(
- 'default' => 0,
- 'type' => PARAM_INT,
- );
- $def['timecreated'] = array(
- 'default' => 0,
- 'type' => PARAM_INT,
- );
- $def['timemodified'] = array(
- 'default' => 0,
- 'type' => PARAM_INT
- );
- $def['usermodified'] = array(
- 'default' => 0,
- 'type' => PARAM_INT
- );
- // List of reserved property names. Mostly because we have methods (getters/setters) which would confict with them.
- // Think about backwards compability before adding new ones here!
- $reserved = array('errors', 'formatted_properties', 'records', 'records_select', 'property_default_value',
- 'property_error_message', 'sql_fields');
- foreach ($def as $property => $definition) {
- // Ensures that the null property is always set.
- if (!array_key_exists('null', $definition)) {
- $def[$property]['null'] = NULL_NOT_ALLOWED;
- }
- // Warn the developers when they are doing something wrong.
- if ($CFG->debugdeveloper) {
- if (!array_key_exists('type', $definition)) {
- throw new coding_exception('Missing type for: ' . $property);
- } else if (isset($definition['message']) && !($definition['message'] instanceof lang_string)) {
- throw new coding_exception('Invalid error message for: ' . $property);
- } else if (in_array($property, $reserved)) {
- throw new coding_exception('This property cannot be defined: ' . $property);
- }
- }
- }
- return $def;
- }
- /**
- * Gets all the formatted properties.
- *
- * Formatted properties are properties which have a format associated with them.
- *
- * @return array Keys are property names, values are property format names.
- */
- final public static function get_formatted_properties() {
- $properties = static::properties_definition();
- $formatted = array();
- foreach ($properties as $property => $definition) {
- $propertyformat = $property . 'format';
- if (($definition['type'] == PARAM_RAW || $definition['type'] == PARAM_CLEANHTML)
- && array_key_exists($propertyformat, $properties)
- && $properties[$propertyformat]['type'] == PARAM_INT) {
- $formatted[$property] = $propertyformat;
- }
- }
- return $formatted;
- }
- /**
- * Gets the default value for a property.
- *
- * This assumes that the property exists.
- *
- * @param string $property The property name.
- * @return mixed
- */
- final protected static function get_property_default_value($property) {
- $properties = static::properties_definition();
- if (!isset($properties[$property]['default'])) {
- return null;
- }
- $value = $properties[$property]['default'];
- if ($value instanceof \Closure) {
- return $value();
- }
- return $value;
- }
- /**
- * Gets the error message for a property.
- *
- * This assumes that the property exists.
- *
- * @param string $property The property name.
- * @return lang_string
- */
- final protected static function get_property_error_message($property) {
- $properties = static::properties_definition();
- if (!isset($properties[$property]['message'])) {
- return new lang_string('invaliddata', 'error');
- }
- return $properties[$property]['message'];
- }
- /**
- * Returns whether or not a property was defined.
- *
- * @param string $property The property name.
- * @return boolean
- */
- final public static function has_property($property) {
- $properties = static::properties_definition();
- return isset($properties[$property]);
- }
- /**
- * Returns whether or not a property is required.
- *
- * By definition a property with a default value is not required.
- *
- * @param string $property The property name.
- * @return boolean
- */
- final public static function is_property_required($property) {
- $properties = static::properties_definition();
- return !array_key_exists('default', $properties[$property]);
- }
- /**
- * Populate this class with data from a DB record.
- *
- * Note that this does not use any custom setter because the data here is intended to
- * represent what is stored in the database.
- *
- * @param \stdClass $record A DB record.
- * @return static
- */
- final public function from_record(stdClass $record) {
- $properties = static::properties_definition();
- $record = array_intersect_key((array) $record, $properties);
- foreach ($record as $property => $value) {
- $this->raw_set($property, $value);
- }
- return $this;
- }
- /**
- * Create a DB record from this class.
- *
- * Note that this does not use any custom getter because the data here is intended to
- * represent what is stored in the database.
- *
- * @return \stdClass
- */
- final public function to_record() {
- $data = new stdClass();
- $properties = static::properties_definition();
- foreach ($properties as $property => $definition) {
- $data->$property = $this->raw_get($property);
- }
- return $data;
- }
- /**
- * Load the data from the DB.
- *
- * @return static
- */
- final public function read() {
- global $DB;
- if ($this->get('id') <= 0) {
- throw new coding_exception('id is required to load');
- }
- $record = $DB->get_record(static::TABLE, array('id' => $this->get('id')), '*', MUST_EXIST);
- $this->from_record($record);
- // Validate the data as it comes from the database.
- $this->validated = true;
- return $this;
- }
- /**
- * Hook to execute before a create.
- *
- * Please note that at this stage the data has already been validated and therefore
- * any new data being set will not be validated before it is sent to the database.
- *
- * This is only intended to be used by child classes, do not put any logic here!
- *
- * @return void
- */
- protected function before_create() {
- }
- /**
- * Insert a record in the DB.
- *
- * @return static
- */
- final public function create() {
- global $DB, $USER;
- if ($this->raw_get('id')) {
- // The validation methods rely on the ID to know if we're updating or not, the ID should be
- // falsy whenever we are creating an object.
- throw new coding_exception('Cannot create an object that has an ID defined.');
- }
- if (!$this->is_valid()) {
- throw new invalid_persistent_exception($this->get_errors());
- }
- // Before create hook.
- $this->before_create();
- // We can safely set those values bypassing the validation because we know what we're doing.
- $now = time();
- $this->raw_set('timecreated', $now);
- $this->raw_set('timemodified', $now);
- $this->raw_set('usermodified', $USER->id);
- $record = $this->to_record();
- unset($record->id);
- $id = $DB->insert_record(static::TABLE, $record);
- $this->raw_set('id', $id);
- // We ensure that this is flagged as validated.
- $this->validated = true;
- // After create hook.
- $this->after_create();
- return $this;
- }
- /**
- * Hook to execute after a create.
- *
- * This is only intended to be used by child classes, do not put any logic here!
- *
- * @return void
- */
- protected function after_create() {
- }
- /**
- * Hook to execute before an update.
- *
- * Please note that at this stage the data has already been validated and therefore
- * any new data being set will not be validated before it is sent to the database.
- *
- * This is only intended to be used by child classes, do not put any logic here!
- *
- * @return void
- */
- protected function before_update() {
- }
- /**
- * Update the existing record in the DB.
- *
- * @return bool True on success.
- */
- final public function update() {
- global $DB, $USER;
- if ($this->raw_get('id') <= 0) {
- throw new coding_exception('id is required to update');
- } else if (!$this->is_valid()) {
- throw new invalid_persistent_exception($this->get_errors());
- }
- // Before update hook.
- $this->before_update();
- // We can safely set those values after the validation because we know what we're doing.
- $this->raw_set('timemodified', time());
- $this->raw_set('usermodified', $USER->id);
- $record = $this->to_record();
- unset($record->timecreated);
- $record = (array) $record;
- // Save the record.
- $result = $DB->update_record(static::TABLE, $record);
- // We ensure that this is flagged as validated.
- $this->validated = true;
- // After update hook.
- $this->after_update($result);
- return $result;
- }
- /**
- * Hook to execute after an update.
- *
- * This is only intended to be used by child classes, do not put any logic here!
- *
- * @param bool $result Whether or not the update was successful.
- * @return void
- */
- protected function after_update($result) {
- }
- /**
- * Saves the record to the database.
- *
- * If this record has an ID, then {@link self::update()} is called, otherwise {@link self::create()} is called.
- * Before and after hooks for create() or update() will be called appropriately.
- *
- * @return void
- */
- final public function save() {
- if ($this->raw_get('id') <= 0) {
- $this->create();
- } else {
- $this->update();
- }
- }
- /**
- * Hook to execute before a delete.
- *
- * This is only intended to be used by child classes, do not put any logic here!
- *
- * @return void
- */
- protected function before_delete() {
- }
- /**
- * Delete an entry from the database.
- *
- * @return bool True on success.
- */
- final public function delete() {
- global $DB;
- if ($this->raw_get('id') <= 0) {
- throw new coding_exception('id is required to delete');
- }
- // Hook before delete.
- $this->before_delete();
- $result = $DB->delete_records(static::TABLE, array('id' => $this->raw_get('id')));
- // Hook after delete.
- $this->after_delete($result);
- // Reset the ID to avoid any confusion, this also invalidates the model's data.
- if ($result) {
- $this->raw_set('id', 0);
- }
- return $result;
- }
- /**
- * Hook to execute after a delete.
- *
- * This is only intended to be used by child classes, do not put any logic here!
- *
- * @param bool $result Whether or not the delete was successful.
- * @return void
- */
- protected function after_delete($result) {
- }
- /**
- * Hook to execute before the validation.
- *
- * This hook will not affect the validation results in any way but is useful to
- * internally set properties which will need to be validated.
- *
- * This is only intended to be used by child classes, do not put any logic here!
- *
- * @return void
- */
- protected function before_validate() {
- }
- /**
- * Validates the data.
- *
- * Developers can implement addition validation by defining a method as follows. Note that
- * the method MUST return a lang_string() when there is an error, and true when the data is valid.
- *
- * protected function validate_propertyname($value) {
- * if ($value !== 'My expected value') {
- * return new lang_string('invaliddata', 'error');
- * }
- * return true
- * }
- *
- * It is OK to use other properties in your custom validation methods when you need to, however note
- * they might not have been validated yet, so try not to rely on them too much.
- *
- * Note that the validation methods should be protected. Validating just one field is not
- * recommended because of the possible dependencies between one field and another,also the
- * field ID can be used to check whether the object is being updated or created.
- *
- * When validating foreign keys the persistent should only check that the associated model
- * exists. The validation methods should not be used to check for a change in that relationship.
- * The API method setting the attributes on the model should be responsible for that.
- * E.g. On a course model, the method validate_categoryid will check that the category exists.
- * However, if a course can never be moved outside of its category it would be up to the calling
- * code to ensure that the category ID will not be altered.
- *
- * @return array|true Returns true when the validation passed, or an array of properties with errors.
- */
- final public function validate() {
- global $CFG;
- // Before validate hook.
- $this->before_validate();
- // If this object has not been validated yet.
- if ($this->validated !== true) {
- $errors = array();
- $properties = static::properties_definition();
- foreach ($properties as $property => $definition) {
- // Get the data, bypassing the potential custom getter which could alter the data.
- $value = $this->raw_get($property);
- // Check if the property is required.
- if ($value === null && static::is_property_required($property)) {
- $errors[$property] = new lang_string('requiredelement', 'form');
- continue;
- }
- // Check that type of value is respected.
- try {
- if ($definition['type'] === PARAM_BOOL && $value === false) {
- // Validate_param() does not like false with PARAM_BOOL, better to convert it to int.
- $value = 0;
- }
- if ($definition['type'] === PARAM_CLEANHTML) {
- // We silently clean for this type. It may introduce changes even to valid data.
- $value = clean_param($value, PARAM_CLEANHTML);
- }
- validate_param($value, $definition['type'], $definition['null']);
- } catch (invalid_parameter_exception $e) {
- $errors[$property] = static::get_property_error_message($property);
- continue;
- }
- // Check that the value is part of a list of allowed values.
- if (isset($definition['choices']) && !in_array($value, $definition['choices'])) {
- $errors[$property] = static::get_property_error_message($property);
- continue;
- }
- // Call custom validation method.
- $method = 'validate_' . $property;
- if (method_exists($this, $method)) {
- // Warn the developers when they are doing something wrong.
- if ($CFG->debugdeveloper) {
- $reflection = new ReflectionMethod($this, $method);
- if (!$reflection->isProtected()) {
- throw new coding_exception('The method ' . get_class($this) . '::'. $method . ' should be protected.');
- }
- }
- $valid = $this->{$method}($value);
- if ($valid !== true) {
- if (!($valid instanceof lang_string)) {
- throw new coding_exception('Unexpected error message.');
- }
- $errors[$property] = $valid;
- continue;
- }
- }
- }
- $this->validated = true;
- $this->errors = $errors;
- }
- return empty($this->errors) ? true : $this->errors;
- }
- /**
- * Returns whether or not the model is valid.
- *
- * @return boolean True when it is.
- */
- final public function is_valid() {
- return $this->validate() === true;
- }
- /**
- * Returns the validation errors.
- *
- * @return array
- */
- final public function get_errors() {
- $this->validate();
- return $this->errors;
- }
- /**
- * Extract a record from a row of data.
- *
- * Most likely used in combination with {@link self::get_sql_fields()}. This method is
- * simple enough to be used by non-persistent classes, keep that in mind when modifying it.
- *
- * e.g. persistent::extract_record($row, 'user'); should work.
- *
- * @param stdClass $row The row of data.
- * @param string $prefix The prefix the data fields are prefixed with, defaults to the table name followed by underscore.
- * @return stdClass The extracted data.
- */
- public static function extract_record($row, $prefix = null) {
- if ($prefix === null) {
- $prefix = str_replace('_', '', static::TABLE) . '_';
- }
- $prefixlength = strlen($prefix);
- $data = new stdClass();
- foreach ($row as $property => $value) {
- if (strpos($property, $prefix) === 0) {
- $propertyname = substr($property, $prefixlength);
- $data->$propertyname = $value;
- }
- }
- return $data;
- }
- /**
- * Load a list of records.
- *
- * @param array $filters Filters to apply.
- * @param string $sort Field to sort by.
- * @param string $order Sort order.
- * @param int $skip Limitstart.
- * @param int $limit Number of rows to return.
- *
- * @return static[]
- */
- public static function get_records($filters = array(), $sort = '', $order = 'ASC', $skip = 0, $limit = 0) {
- global $DB;
- $orderby = '';
- if (!empty($sort)) {
- $orderby = $sort . ' ' . $order;
- }
- $records = $DB->get_records(static::TABLE, $filters, $orderby, '*', $skip, $limit);
- $instances = array();
- foreach ($records as $record) {
- $newrecord = new static(0, $record);
- array_push($instances, $newrecord);
- }
- return $instances;
- }
- /**
- * Load a single record.
- *
- * @param array $filters Filters to apply.
- * @return false|static
- */
- public static function get_record($filters = array()) {
- global $DB;
- $record = $DB->get_record(static::TABLE, $filters);
- return $record ? new static(0, $record) : false;
- }
- /**
- * Load a list of records based on a select query.
- *
- * @param string $select
- * @param array $params
- * @param string $sort
- * @param string $fields
- * @param int $limitfrom
- * @param int $limitnum
- * @return static[]
- */
- public static function get_records_select($select, $params = null, $sort = '', $fields = '*', $limitfrom = 0, $limitnum = 0) {
- global $DB;
- $records = $DB->get_records_select(static::TABLE, $select, $params, $sort, $fields, $limitfrom, $limitnum);
- // We return class instances.
- $instances = array();
- foreach ($records as $key => $record) {
- $instances[$key] = new static(0, $record);
- }
- return $instances;
- }
- /**
- * Return the list of fields for use in a SELECT clause.
- *
- * Having the complete list of fields prefixed allows for multiple persistents to be fetched
- * in a single query. Use {@link self::extract_record()} to extract the records from the query result.
- *
- * @param string $alias The alias used for the table.
- * @param string $prefix The prefix to use for each field, defaults to the table name followed by underscore.
- * @return string The SQL fragment.
- */
- public static function get_sql_fields($alias, $prefix = null) {
- global $CFG;
- $fields = array();
- if ($prefix === null) {
- $prefix = str_replace('_', '', static::TABLE) . '_';
- }
- // Get the properties and move ID to the top.
- $properties = static::properties_definition();
- $id = $properties['id'];
- unset($properties['id']);
- $properties = array('id' => $id) + $properties;
- foreach ($properties as $property => $definition) {
- $as = $prefix . $property;
- $fields[] = $alias . '.' . $property . ' AS ' . $as;
- // Warn developers that the query will not always work.
- if ($CFG->debugdeveloper && strlen($as) > 30) {
- throw new coding_exception("The alias '$as' for column '$alias.$property' exceeds 30 characters" .
- " and will therefore not work across all supported databases.");
- }
- }
- return implode(', ', $fields);
- }
- /**
- * Count a list of records.
- *
- * @param array $conditions An array of conditions.
- * @return int
- */
- public static function count_records(array $conditions = array()) {
- global $DB;
- $count = $DB->count_records(static::TABLE, $conditions);
- return $count;
- }
- /**
- * Count a list of records.
- *
- * @param string $select
- * @param array $params
- * @return int
- */
- public static function count_records_select($select, $params = null) {
- global $DB;
- $count = $DB->count_records_select(static::TABLE, $select, $params);
- return $count;
- }
- /**
- * Check if a record exists by ID.
- *
- * @param int $id Record ID.
- * @return bool
- */
- public static function record_exists($id) {
- global $DB;
- return $DB->record_exists(static::TABLE, array('id' => $id));
- }
- /**
- * Check if a records exists.
- *
- * @param string $select
- * @param array $params
- * @return bool
- */
- public static function record_exists_select($select, array $params = null) {
- global $DB;
- return $DB->record_exists_select(static::TABLE, $select, $params);
- }
- }