如何解决mysqli_fetch_array()错误

Question

当我运行页面时它会抛出此错误,但我不知道为什么:

警告: mysqli_fetch_array()期望参数1为mysqli_result,第234行的C:\ wamp\www\SAMS\record.php中给出布尔值

这是我的查询:

$data = "SELECT *, (SELECT SUM(studAtt_endTime - studAtt_startTime) FROM studentAttendance WHERE studAtt_status='0')
                FROM studentAttendance INNER JOIN student ON studentAttendance.student_stud_matric=student.stud_matric
                INNER JOIN course ON studentAttendance.course_course_code=course.course_code
                WHERE WHERE studentAttendance.course_course_code LIKE '%$_GET[course]%' GROUP BY student_stud_matric;";

Answer 1

你'WHERE'的查询有两倍.删除另一个.