colleague / study-project · Files

<?php
/**
 * 随机答卷详情临时表
 * Created by PhpStorm.
 * User: yingcai
 * Date: 2017/8/9
 * Time: 下午3:41
 */

namespace Common\Model;


class AnswerTempModel extends AbstractModel
{

    public function get_answer_temp($ep_id)
    {
        $params[] = $ep_id;
        $params[] = AnswerModel::ST_DELETE;
        $params[] = QY_DOMAIN;
        
        // MySQL随机获取一条数据（此SQL仅适用随机一条，不能随机多条，多条会出现主键连续）
        $sql = 'SELECT * FROM oa_exam_answer_temp AS t1 JOIN (SELECT ROUND(RAND() * ((SELECT MAX(eat_id) FROM `oa_exam_answer_temp`)-(SELECT MIN(eat_id) FROM oa_exam_answer_temp))+(SELECT MIN(eat_id) FROM oa_exam_answer_temp)) AS eat_id) AS t2 WHERE t1.eat_id >= t2.eat_id AND t1.ep_id=? AND t1.status<? AND domain=? ORDER BY t1.eat_id LIMIT 1';

        return $this->_m->fetch_array($sql, $params);
    }
}