MySQL GROUP unless value equals 0 - mysql

Question

I would like a query that groups the results together unless the value of job_num = 0 but I have been unable to work out how to do it.
This is my query as it stands (and doesn't work, I get a SQL error)...
SELECT SQL_CALC_FOUND_ROWS * FROM calls
WHERE parent_id = '$term' GROUP BY IF (job_num != 0)
ORDER BY date_start DESC LIMIT $page_position, $item_per_page
I have tried replacing job_num != 0 with job_num IS NOT NULL and get the same result.
The rest of the query works fine until I tried to exclude the job_num != 0
This a simplified version of the table
id | call_ref | job_num
_______________________
1 | 123445 | 2389
_______________________
2 | 342537 | 0
_______________________
3 | 876483 | 2389
_______________________
4 | 644686 | 5643
_______________________
5 | 654532 | 0
I would like to group the rows where the job_num != 0 but I still want to display the rows where job_num = 0 just not grouped together. The call_ref is not unique and there are a further 31 columns in the table I need the values of.
Using the above example rows with ids 1 and 3 would be grouped and 2,4 and 5 would still return results but not grouped.
The results I would like...
1 and 3 grouped (because the job_nums are the same but != 0)
2, 4, 5 not grouped

Answer 1

Can you try it with UNION?
(SELECT SQL_CALC_FOUND_ROWS * FROM calls
WHERE parent_id = '$term' where job_num != 0 GROUP BY (job_num)
ORDER BY date_start DESC LIMIT $page_position, $item_per_page)
UNION
(SELECT SQL_CALC_FOUND_ROWS * FROM calls
WHERE parent_id = '$term' where job_num = 0
ORDER BY date_start DESC LIMIT $page_position, $item_per_page);

Answer 2

if you use this request in PHP code Try
SELECT SQL_CALC_FOUND_ROWS FROM calls
WHERE parent_id = \'$term\' GROUP BY IF job_num <> 0
ORDER BY date_start DESC LIMIT $page_position, $item_per_page;

Answer 3

Try this one
SELECT *
FROM
(SELECT SQL_CALC_FOUND_ROWS *
FROM calls
WHERE parent_id = '$term'
AND job_num != 0
GROUP BY job_num
UNION SELECT SQL_CALC_FOUND_ROWS *
FROM calls
WHERE parent_id = '$term'
AND job_num = 0) AS T
ORDER BY date_start DESC LIMIT $page_position,
$item_per_page

Answer 4

Based on this comment:
#mcNets because ideally I'd like to display the results with job_num
!= 0, I just don't want the results with that value grouped together
You do not want group by (although I don't understand what "that value" refers to). I do note this is in direct contradiction of the first sentence of the question.
Does this do what you want?
SELECT SQL_CALC_FOUND_ROWS c.*
FROM calls c
WHERE c.parent_id = '$term' AND job_num <> 0
ORDER BY date_start DESC
LIMIT $page_position, $item_per_page;
EDIT:
It occurs to me that you might just want rows with the value of 0 to appear together and the rest to appear together. If that is the case, put the condition in the ORDER BY:
SELECT SQL_CALC_FOUND_ROWS c.*
FROM calls c
WHERE c.parent_id = '$term'
ORDER BY (job_num = 0), date_start DESC
LIMIT $page_position, $item_per_page;

Answer 5

You can use a derived table for the main query, then LEFT JOIN it on to the table that you want to display multiple rows for. For example:
SELECT *
FROM (
SELECT a.account_id 'CRM ID', a.lead_status 'Status', a.account_name 'Client Name', DATE_FORMAT(DATE_ADD(FROM_UNIXTIME(0), INTERVAL a.date_of_birth SECOND), '%d-%m-%Y') AS 'DOB', a.postcode 'Postcode',
a.phone 'Phone #.', a.email 'Email', IFNULL(i.invoice_date, 'Never') AS 'Last Invoice'
FROM mydb.invoices i
RIGHT JOIN mydb.members m ON i.member_id = m.member_id
RIGHT JOIN mydb.accounts a ON m.crm_id = a.account_id
WHERE (i.invoice_status LIKE 'SAVE%' OR i.invoice_date IS NULL)
AND a.lead_status IN ('SIGNED UP', 'BILLING')
AND a.account_position != 'DELETED'
GROUP BY a.account_id
) x
LEFT JOIN mydb.account_owners o ON x.`CRM ID` = o.account_id
In this query, the final LEFT JOIN is the one that makes the row display more than once, despite the GROUP BY, e.g.:
Aside: ignore the fact that the columns in the above query have got 'friendly' names. This query is taken from a reporting tool that shows the columns based upon what SQL returns :)