$sql = 'SELECT s2.id, s2.course, s2.sequence

                FROM mdl_course_sections s2

                JOIN(

                    SELECT DISTINCT s.id

                    FROM

                    {course_modules} cm

                    JOIN {course_sections} s

                    ON

                        cm.course = s.course

                    WHERE cm.section != s.id AND ' . $sequenceconcat . ' LIKE ' . $moduleconcat . '

                ) d

                ON s2.id = d.id';

        $coursesections = $DB->get_recordset_sql($sql);

Debug info: Table 'moodlegjb.mdl_course_sections' doesn't exist

SELECT s2.id, s2.course, s2.sequence 

FROM mdl_course_sections s2 

JOIN( 

SELECT DISTINCT s.id 

FROM 

mdl23_course_modules cm 

JOIN mdl23_course_sections s 

ON 

cm.course = s.course 

WHERE cm.section != s.id AND CONCAT(',', s.sequence, ',') LIKE CONCAT('%,', cm.id, ',%') 

) d 

ON s2.id = d.id

[array (

)] 

Error code: dmlreadexception

Stack trace:

line 407 of \lib\dml\moodle_database.php: dml_read_exception thrown

line 903 of \lib\dml\mysqli_native_moodle_database.php: call to moodle_database->query_end()

line 1091 of \lib\db\upgrade.php: call to mysqli_native_moodle_database->get_recordset_sql()

line 1480 of \lib\upgradelib.php: call to xmldb_main_upgrade()

line 275 of \admin\index.php: call to upgrade_core()