How to use Union Inner Join Query?

Question

I have a query that a previous employee created and is working correctly. However, I need to add a table to it called 'info' and am having a hard time with it. The 'info' table has a user column that should match the user_id column in the users table.

The info table has columns such as user (which is the user id), company, phone, fullname. The query currently emails out a to users that are registered to a specific tender. Then a log file is created and in that log file I need to display information from the info table such as company, phone, and fullname.

I've tried adding it after the first INNER JOIN like this:

INNER JOIN info
 ON info.user = users.user_id

The query will run but it won't grab any info from the info table when I try to display it.

Below is the query that works:

$sql = '
        SELECT users.user_id
             , users.username
          FROM users
        INNER
          JOIN registrations
            ON registrations.user = users.user_id
           AND registrations.tender = '.mysql_real_escape_string($tender).'

        UNION 
        SELECT users.user_id
             , users.username
          FROM users

        INNER
          JOIN user_divisions
            ON user_divisions.user = users.user_id

        INNER
          JOIN tender_divisions
            ON tender_divisions.division = user_divisions.division    
           AND tender_divisions.tender = '.mysql_real_escape_string($tender).'

        WHERE
            users.verified = 1 
        GROUP 
            BY users.user_id
        ';

Answer 1

Usent the same format
Make sure that all user are exist in users table to show all the info data
SELECT users.user_id
, users.username
FROM info
INNER
JOIN users
ON info.user =users.user_I'd

Answer 2

Based on your input, this should work (I have formatted the SQL to match my style)

        SELECT users.user_id, users.username, info.*
        FROM users
          INNER JOIN registrations ON  registrations.user = users.user_id
                                   AND registrations.tender = '.mysql_real_escape_string($tender).'
          INNER JOIN info ON info.user = users.user_id    

    UNION 

        SELECT users.user_id , users.username, info.*
        FROM users
          INNER JOIN user_divisions ON user_divisions.user = users.user_id
          INNER JOIN tender_divisions ON  tender_divisions.division = user_divisions.division    
                                      AND tender_divisions.tender = '.mysql_real_escape_string($tender).'
          INNER JOIN info ON info.user = users.user_id            
        WHERE users.verified = 1 
        GROUP BY users.user_id

There's no reason for it to not work if the initial query is working fine.

If it doesn't return any record, it means that you don't have a match between your user table and your info table. You can change the INNER JOIN to a LEFT JOIN to verify this.

---

Remark:

I don't like the GROUP BY in the last query. It works with MySQL but this is not ANSI standard, and you might get into issues if your move to another DB with ONLY_FULL_GROUP_BY mode activated

You should have the same columns in the SELECT than in the GROUP BY . If the aim is to remove duplicates (it looks like as you don't use an aggregate function in the SELECT ) then you should use DISTINCT instead

Worth a read : MySQL Handling of GROUP BY