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POQuery Returns No Results Only When ORDER BY Added
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  1. POQuery Returns No Results Only When ORDER BY Added
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    copied!<p>I have a table with the following schema:</p> <p><strong>people_stages</strong></p> <pre><code>id | person_id | stage_id | created 1 | 1 | 1 | 2013-09-01 00:00:00 2 | 1 | 2 | 2013-09-02 00:00:00 3 | 1 | 3 | 2013-09-03 00:00:00 </code></pre> <p>I have created the following query to select the most recent stage grouped by person:</p> <pre><code>SELECT * FROM people Person LEFT JOIN people_stages PersonStage ON PersonStage.person_id = Person.id WHERE PersonStage.created = (SELECT MAX(people_stages.created) FROM people_stages GROUP BY person_id HAVING person_id = PersonStage.person_id); </code></pre> <p>It works fine, however, if I try to ORDER BY a field in the Person table:</p> <pre><code>SELECT * FROM people Person LEFT JOIN people_stages PersonStage ON PersonStage.person_id = Person.id WHERE PersonStage.created = (SELECT MAX(people_stages.created) FROM people_stages GROUP BY person_id HAVING person_id = PersonStage.person_id) ORDER BY Person.last_name; </code></pre> <p>It returns 0 results. </p> <p>Could anyone provide some insight, please?</p> <p>Thanks!</p> <p><strong>EDIT: Structure of <code>people</code></strong></p> <pre><code>+----------------------------+--------------------------------------------------------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +----------------------------+--------------------------------------------------------------+------+-----+---------+----------------+ | id | bigint(20) | NO | PRI | NULL | auto_increment | | internal_id | varchar(50) | NO | MUL | NULL | | | public_id | varchar(30) | NO | | NULL | | | counselor_id | bigint(20) | NO | | NULL | | | term_id | int(11) | NO | MUL | NULL | | | program_id | int(11) | NO | | NULL | | | person_type_id | int(11) | NO | MUL | NULL | | | first_name | varchar(100) | NO | | NULL | | | middle_name | varchar(100) | NO | | NULL | | | last_name | varchar(100) | NO | | NULL | | | photo_url | varchar(255) | NO | | NULL | | | gender | enum('m','f','u') | NO | | NULL | | | date_of_birth | date | NO | | NULL | | | address | varchar(255) | NO | | NULL | | | address_apt | varchar(100) | NO | | NULL | | | address_city | varchar(100) | NO | | NULL | | | address_state | varchar(100) | NO | | NULL | | | address_state_intl | varchar(255) | NO | | NULL | | | address_zip | varchar(25) | NO | | NULL | | | address_country | varchar(100) | NO | | NULL | | | address_verified | tinyint(1) | NO | | NULL | | | address_latitude | varchar(100) | NO | | NULL | | | address_longitude | varchar(100) | NO | | NULL | | | address_position | point | NO | MUL | NULL | | | address_distance | smallint(6) | NO | | NULL | | | social_facebook | mediumtext | NO | | NULL | | | social_twitter | varchar(255) | NO | | NULL | | | social_instagram | varchar(255) | NO | | NULL | | | phone_cell | varchar(25) | NO | | NULL | | | phone_cell_clean | varchar(25) | YES | | NULL | | | phone_work | varchar(25) | NO | | NULL | | | phone_work_clean | varchar(25) | NO | | NULL | | | permission_to_text | tinyint(1) | NO | | NULL | | | permission_to_text_confirm | tinyint(1) | NO | | NULL | | | phone_home | varchar(25) | NO | | NULL | | | phone_home_clean | varchar(25) | YES | | NULL | | | email_address | varchar(255) | NO | | NULL | | | permission_to_email | tinyint(1) | NO | | NULL | | | preferred_contact | enum('phone_home','phone_cell','text_cell','email','postal') | NO | | NULL | | | parent_first_name | varchar(100) | NO | | NULL | | | parent_last_name | varchar(100) | NO | | NULL | | | parent_email | varchar(255) | NO | | NULL | | | hs_name | varchar(255) | NO | | NULL | | | hs_homeschooled | tinyint(1) | NO | | NULL | | | hs_ceeb_id | varchar(100) | NO | | NULL | | | hs_grad_year | varchar(4) | NO | | NULL | | | coll_name | varchar(255) | NO | | NULL | | | coll_ceeb_id | varchar(100) | NO | | NULL | | | coll_major | varchar(255) | NO | | NULL | | | coll_year | varchar(20) | NO | | NULL | | | counselor_read | tinyint(1) | NO | | NULL | | | source | varchar(100) | NO | | NULL | | | entry_method | varchar(100) | NO | | NULL | | | erp_processed | tinyint(1) | NO | | NULL | | | created | datetime | NO | | NULL | | | modified | datetime | NO | | NULL | | +----------------------------+--------------------------------------------------------------+------+-----+---------+----------------+ </code></pre>
 

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