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See Release Notes
Long Term Support Release

  • Bug fixes for general core bugs in 4.1.x will end 13 November 2023 (12 months).
  • Bug fixes for security issues in 4.1.x will end 10 November 2025 (36 months).
  • PHP version: minimum PHP 7.4.0 Note: minimum PHP version has increased since Moodle 4.0. PHP 8.0.x is supported too.
<?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/>.

declare(strict_types=1);

namespace core_reportbuilder\local\aggregation;

use lang_string;
use core_reportbuilder\local\helpers\database;

/**
 * Column group concatenation distinct aggregation type
 *
 * @package     core_reportbuilder
 * @copyright   2021 Paul Holden <paulh@moodle.com>
 * @license     http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */
class groupconcatdistinct extends groupconcat {

    /**
     * Return aggregation name
     *
     * @return lang_string
     */
    public static function get_name(): lang_string {
        return new lang_string('aggregationgroupconcatdistinct', 'core_reportbuilder');
    }

    /**
< * This aggregation can be performed on all non-timestamp columns in MySQL and Postgres only
> * This aggregation can be performed on all non-timestamp columns in MySQL, Postgres and Oracle only
* * @param int $columntype * @return bool */ public static function compatible(int $columntype): bool { global $DB; $dbsupportedtype = in_array($DB->get_dbfamily(), [ 'mysql', 'postgres',
> 'oracle',
]); return $dbsupportedtype && parent::compatible($columntype); } /** * Return the aggregated field SQL * * @param string $field * @param int $columntype * @return string */ public static function get_field_sql(string $field, int $columntype): string { global $DB;
< // DB limitations mean we only support MySQL and Postgres, and each handle it differently.
$fieldsort = database::sql_group_concat_sort($field);
> if ($DB->get_dbfamily() === 'postgres') { > // Postgres handles group concatenation differently in that it requires the expression to be cast to char, so we can't if ($fieldsort !== '') { > // simply pass "DISTINCT {$field}" to the {@see \moodle_database::sql_group_concat} method in all cases.
$fieldsort = "ORDER BY {$fieldsort}";
> $field = $DB->sql_cast_to_char($field);
}
< return "STRING_AGG(DISTINCT CAST({$field} AS VARCHAR), '" . self::FIELD_VALUE_DELIMETER . "' {$fieldsort})";
> return "STRING_AGG(DISTINCT {$field}, '" . self::FIELD_VALUE_DELIMETER . "' {$fieldsort})";
} else { return $DB->sql_group_concat("DISTINCT {$field}", self::FIELD_VALUE_DELIMETER, $fieldsort); } } }