我在一个网站上工作，它要求我只在一个表中显示具体的课程，并按年份进行具体说明。
以下是我表格中的一些细节：
桌上学生
stdid、stdcoursedesc、accessdate
12211，飞机维修许可证计划？欧洲广告标准联盟第66部分，2018-3-6
12212，飞机维修许可证计划？欧洲广告标准联盟第66部分，2015-8-6
12213，飞机维修技术（制造）文凭，2017-3-1
12214，工商管理硕士（创业），2018-1-16
12215，飞机维修许可证计划？欧洲广告标准联盟第66部分，2015-10-1
12216，飞机维修许可证计划？欧洲广告标准联盟第66部分，2016-12-10
12217，哲学博士（制造），2016-5-14
我只管理代码，直到这个，但当然它只显示课程。

SELECT CONCAT(`stdCourseDesc`, ', ', `accessDate`) AS byYear FROM student WHERE `stdCourseDesc` = 'Aircraft Maintenance License Program ? EASA Part 66'

我试过但失败了。

SELECT CONCAT(stdCourseDesc, ', ', accessDate) AS byYear FROM student where `stdCourseDesc` = 'Aircraft Maintenance License Program ? EASA Part 66', YEAR(`accessDate`)=2015

我将使用这个代码来显示输出

$conn = new mysqli ('localhost', 'root', '', 'dashboard');

$aircraftyear2015 = $conn ->query ("SELECT CONCAT(`stdCourseDesc`, ', ', 
`accessDate`) AS byYear FROM student WHERE `stdCourseDesc` = 'Aircraft 
Maintenance License Program ? EASA Part 66'");
$aircraftyear2016 = $conn ->query ("SELECT CONCAT(`stdCourseDesc`, ', ', 
`accessDate`) AS byYear FROM student WHERE `stdCourseDesc` = 'Aircraft 
Maintenance License Program ? EASA Part 66'");
$aircraftyear2017 = $conn ->query ("SELECT CONCAT(`stdCourseDesc`, ', ', 
`accessDate`) AS byYear FROM student WHERE `stdCourseDesc` = 'Aircraft 
Maintenance License Program ? EASA Part 66'");
$aircraftyear2018 = $conn ->query ("SELECT CONCAT(`stdCourseDesc`, ', ', 
`accessDate`) AS byYear FROM student WHERE `stdCourseDesc` = 'Aircraft 
Maintenance License Program ? EASA Part 66'");

$tot_aircraftyear2015 = mysqli_num_rows($aircraftyear2016);
$tot_aircraftyear2016 = mysqli_num_rows($aircraftyear2017);
$tot_aircraftyear2017 = mysqli_num_rows($aircraftyear2016);
$tot_aircraftyear2018 = mysqli_num_rows($aircraftyear2017);

<?php echo $tot_aircraftyear2015; ?>
<?php echo $tot_aircraftyear2016; ?>
<?php echo $tot_aircraftyear2017; ?>
<?php echo $tot_aircraftyear2018; ?>

我要如何在一个mysql表中按特定年份过滤特定课程？
我的代码可以用来显示数据吗？先谢谢你