Debug info: Data too long for column 'value' at row 1
UPDATE mdl_user_preferences SET value = ? WHERE id = ?
[array (
0 => 'a:2:{s:14:"aggregatesonly";a:15:

{i:0;s:2:"14";i:1;s:2:"15";i:3;s:2:"20";i:6;s:2:"26";i:8;s:2:"17";i:10;s:2:"24";i:11;s:2:"25";i:12;s:2:"27";i:13;s:2:"28";i:14;s:2:"21";i:15;s:2:"16";i:16;s:2:"19";i:17;s:2:"29";i:18;s:2:"23";i:19;s:2:"38";}

s:10:"gradesonly";a:0:{}}',
1 => '463',
)]
Stack trace:

• line 394 of /lib/dml/moodle_database.php: dml_write_exception thrown
• line 1037 of /lib/dml/mysqli_native_moodle_database.php: call to moodle_database->query_end()
• line 1441 of /lib/dml/moodle_database.php: call to mysqli_native_moodle_database->set_field_select()
• line 1414 of /lib/moodlelib.php: call to moodle_database->set_field()
• line 1518 of /grade/report/grader/lib.php: call to set_user_preference()
• line 104 of /grade/report/grader/index.php: call to grade_report_grader::process_action()