SELECT
    `TaskRefUser`.`id`,
    `TaskRefUser`.`status` AS `task_status`,
    `TaskRefUser`.`is_tutor`,
    `TaskRefUser`.`mark`,
    `TaskRefUser`.`date_start`,
    `TaskRefUser`.`date_finish`,
    `user`.`id` AS `user.id`,
    `user`.`firstname` AS `user.firstname`,
    `user`.`secondname` AS `user.secondname`,
    `user`.`patronymic` AS `user.patronymic`,
    `user`.`login` AS `user.login`,
    `user`.`tags` AS `user.tags`,
    `user`.`department` AS `user.department`,
    `user`.`position` AS `user.position`,
    `user`.`city` AS `user.city`,
    `user`.`is_chief` AS `user.is_chief`,
    `user`.`is_active` AS `user.is_active`,
    `user`.`email` AS `user.email`,
    `task`.`id` AS `task.id`,
    `task`.`result_mode` AS `task.result_mode`
FROM
    `els_tasks_ref_users` AS `TaskRefUser`
        INNER JOIN
    `cms_users` AS `user` ON `TaskRefUser`.`user_id` = `user`.`id`
        INNER JOIN
    `els_tasks` AS `task` ON `TaskRefUser`.`task_id` = `task`.`id`
WHERE
    `TaskRefUser`.`is_tutor` = TRUE
		AND `user`.`is_deleted` = FALSE
        AND `task`.`is_deleted` != 'true'
        AND `task`.`site_id` = 3
        AND `task`.`type` = 'meetup'
        AND `TaskRefUser`.`task_id` = 20878
LIMIT 0 , 10;