PHP ничего не отображает для ответа JSON

У меня есть БД по имени - посещаемость, которая имеет 2 таблицы

CREATE TABLE 'conference_schedule' (
  'id' int(5) NOT NULL,
  'session' varchar(1024) DEFAULT NULL,
  'start' timestamp NULL DEFAULT NULL,
  'end' timestamp NULL DEFAULT NULL,
  'actstart' timestamp NULL DEFAULT NULL,
  'actend' timestamp NULL DEFAULT NULL,
  'room' varchar(1024) DEFAULT NULL,
  'processed' int(1) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

INSERT INTO 'conference_schedule' ('id', 'session', 'start', 'end', 'actstart', 'actend', 'room', 'processed') VALUES
(1, 'Innovation - From Strategy Through Tactical To Operational', '2018-05-19 21:30:00', '2018-05-20 00:30:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Cliftons Melbourne', 0),
(2, 'Story Telling for Leaders - How To Influence, Engage and Inspire', '2018-05-19 21:30:00', '2018-05-20 05:30:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Cliftons Melbourne', 0),
(3, 'Speak And Be Heard – Strategies And Skills To Be Heard When It\ Difficult To Be Heard', '2018-05-19 21:30:00', '2018-05-20 05:30:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Cliftons Melbourne', 0),
(4, 'Agile & Lean - What You Really Need To Know And Why', '2018-05-19 21:30:00', '2018-05-20 05:30:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Cliftons Melbourne', 0),
(5, 'Overcoming The Global Epidemic Of Dysfunctional Organisations And Disengaged Employees', '2018-05-19 21:30:00', '2018-05-20 00:30:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Cliftons Melbourne', 0),
(6, 'Fast - Track PMI - ACP Agile Certified Practitioner', '2018-05-19 21:30:00', '2018-05-20 05:30:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Cliftons Melbourne', 0),
(7, 'Think With Your Hands: Performance Management - A Master Class Facilitated With Lego Serious Play', '2018-05-20 01:30:00', '2018-05-20 05:30:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Cliftons Melbourne', 0),
(8, 'Opening Ceremony', '2018-05-20 20:30:00', '2018-05-20 20:45:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(9, 'Opening Speech', '2018-05-20 20:45:00', '2018-05-20 21:00:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(10, 'Scrappy Design Thinking: Simple Rules, Practical Tools', '2018-05-20 21:00:00', '2018-05-20 21:45:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(11, 'Managing Diversity From The Inside And Out', '2018-05-20 21:45:00', '2018-05-20 21:15:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(12, 'If You Met A Goldfish - Effective Communication For A Diverse Workplace', '2018-05-20 22:45:00', '2018-05-20 23:30:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(13, 'How PMO Maturity Assessment Can Create A Road Map For Your Future PMO', '2018-05-20 22:45:00', '2018-05-20 23:35:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(14, 'Cyber Security - Risk and Growth #TrueStory', '2018-05-20 22:45:00', '2018-05-20 23:35:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(15, 'The Industry 4.0 Art Of War - Superior Performance Leadership 4.0 Through Diversity & Wellbeing', '2018-05-20 23:35:00', '2018-05-21 00:15:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(16, 'PMI Australia Panel Discussion: Gender Diversity - Fact or Fiction', '2018-05-21 01:15:00', '2018-05-21 02:05:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(17, 'Diversity @ Work: A Session Facilitated With Lego Serious Play', '2018-05-21 01:15:00', '2018-05-21 02:50:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(18, 'Complexity In ICT Enabled Change - Practical Appraches', '2018-05-21 01:15:00', '2018-05-21 02:50:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(19, 'The Value Of Project Management - PMI\ 2017 Pulse Of The Profession', '2018-05-21 03:15:00', '2018-05-21 04:00:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(20, 'The True Story Of A Life Lost And Found', '2018-05-21 04:00:00', '2018-05-21 05:00:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(21, 'Opening Speech', '2018-05-21 20:45:00', '2018-05-21 21:00:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(22, 'Storytelling: A Project Management Superpower', '2018-05-21 21:00:00', '2018-05-21 21:45:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(23, 'Let Yourself Be Heard And Make A Difference', '2018-05-21 22:45:00', '2018-05-21 23:30:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(24, 'Program Management: A New Australian Renaissance - And A Critical Element Of Our Economy And Security', '2018-05-21 22:45:00', '2018-05-21 23:30:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(25, 'Build Your Project Management Career Brand By Improving Linkedin Performance', '2018-05-21 22:45:00', '2018-05-21 23:30:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(26, 'Methodology Battles Is Making Project Delivery Complex - But It Shouldn\'t', '2018-05-21 23:35:00', '2018-05-22 00:20:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(27, 'Executive Leadership: Mindset Is The Biggest Issue! Why Is This And How Can We Tackle It?', '2018-05-21 23:35:00', '2018-05-22 00:15:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(28, 'Agile And The Future Of Project Management', '2018-05-22 01:15:00', '2018-05-22 02:05:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(29, 'Australia\ Newest Radio Telescope - Project Theory And Practical Delivery', '2018-05-22 01:15:00', '2018-05-22 02:05:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(30, 'The Value Of Being Human In A Future Of Artifical Intelligence And Automation', '2018-05-22 02:05:00', '2018-05-22 02:50:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(31, 'Will Robots Steal My Job?', '2018-05-22 02:05:00', '2018-05-22 02:50:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0),
(32, 'The Great Debate', '2018-05-22 03:15:00', '2018-05-22 03:45:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', 'Crown Melbourne', 0);

ALTER TABLE 'conference_schedule'
  ADD PRIMARY KEY ('id');

ALTER TABLE 'conference_schedule'
  MODIFY 'id' int(5) NOT NULL AUTO_INCREMENT, AUTO_INCREMENT=33;
COMMIT;

а также

CREATE TABLE 'users' (
  'id' int(5) NOT NULL,
  'pmiid' int(10) DEFAULT NULL,
  'user_name' varchar(512) DEFAULT NULL,
  'user_email' varchar(512) DEFAULT NULL,
  'user_num' int(10) DEFAULT NULL,
  'user_org' varchar(512) DEFAULT NULL,
  'user_mac' varchar(128) DEFAULT NULL,
  'user_flag' int(3) DEFAULT NULL,
  'user_percent' int(3) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

INSERT INTO 'users' ('id', 'pmiid', 'user_name', 'user_email', 'user_num', 'user_org', 'user_mac', 'user_flag', 'user_percent') VALUES
(17, 12345, 'Hariharan Thiagarajan', '[email protected]', 224596236, 'Electronic Partners', 'FD E7 A0 26 39 77', 0, 0),
(18, 67890, 'Ulaganathan Natarajan', '[email protected]', 2102920557, 'Electronic Partners', 'F2 35 1D E6 8C 63', 0, 0),
(19, 13579, 'Richard', '[email protected]', 123456789, 'Electronic Partners', 'EE CA 10 52 99 80', 0, 0),
(20, 24680, 'Shankar Subramanian', '[email protected]', 21489993, 'Electronic Partners', 'D4 13 A2 0C B5 90', 0, 0);

ALTER TABLE 'users'
  ADD PRIMARY KEY ('id');

ALTER TABLE 'users'
  MODIFY 'id' int(5) NOT NULL AUTO_INCREMENT, AUTO_INCREMENT=21;
COMMIT;

Я попытался создать API JSON для обеих таблиц, и это были файлы PHP

Для таблицы пользователей

<?php
    include("database/db_conection.php");
    $query="SELECT * FROM 'users'";
    $run=mysqli_query($dbcon,$query);
    while($row=mysqli_fetch_assoc($run))
    {
        $user[] = $row;
    }
    $myJSON=json_encode($user);
    echo $myJSON;
?>

Что отображается - Примечание: я установил JSON Viewer Extension для Chrome

Проблема возникает, когда я пытаюсь сделать то же самое для таблицы conference_schedule, я ничего не получаю - нет ошибки, пустой страницы

Для конференц-зала

<?php
    include("database/db_conection.php");
    $query="SELECT * FROM 'conference_schedule'";
    $run=mysqli_query($dbcon,$query);
    while($row=mysqli_fetch_assoc($run))
    {
        $user[] = $row;
    }
    $myJSON=json_encode($user);
    echo $myJSON;
?>

За исключением изменения имени таблицы, ничего больше не меняется, но все же это то, что я получаю.

Что, я здесь пропал или что здесь не так?

Заранее спасибо