Getting the last result of a bug that has been resolved

Question

I have been trying to get a status so i can find out how long has been taking for a bug change its status do 'resolved', so for i have the following SQL:

select bug.id,
       bug.project_id,
       DATEDIFF (FROM_UNIXTIME(his.date_modified), FROM_UNIXTIME(date_submitted)) as dias_resolucao,
       DATE_FORMAT(FROM_UNIXTIME(his.date_modified), '%Y-%m') as ano_mes
from mantis_bug_table bug
left join mantis_project_table pro on bug.project_id = pro.id
left join mantis_custom_field_string_table cus on bug.id = cus.bug_id
left join mantis_bug_history_table his on bug.id = his.bug_id
where bug.category_id = 1 and
      (cus.field_id=1 or cus.field_id is null) and      
      his.new_value = 80 and 
      his.field_name = 'status' and                 
      bug.id = 5171 and
      cus.value='Sim'      
having his.date_modified = max(his.date_modified)

The problem is that i'm unaware why does this print the following error:

[SELECT - 0 row(s), 0.000 secs]  
[Error Code: 1054, SQL State: 42S22]  
Unknown column 'his.date_modified' in 'having clause'

Running the same SQL, without the having clause brings me the following result:

╔══════╦════════════╦════════════════╦═════════╗
║  id  ║ project_id ║ dias_resolucao ║ ano_mes ║
╠══════╬════════════╬════════════════╬═════════╣
║ 5171 ║          4 ║             17 ║ 2012-12 ║
║ 5171 ║          4 ║             18 ║ 2012-12 ║
╚══════╩════════════╩════════════════╩═════════╝

Any help is appreciated.

Answer 1

Try it.

SELECT his.date_modified, bug.id,
       bug.project_id,
       DATEDIFF (FROM_UNIXTIME(his.date_modified), FROM_UNIXTIME(date_submitted)) AS dias_resolucao,
       DATE_FORMAT(FROM_UNIXTIME(his.date_modified), '%Y-%m') AS ano_mes
FROM mantis_bug_table bug
LEFT JOIN mantis_project_table pro ON bug.project_id = pro.id
LEFT JOIN mantis_custom_field_string_table cus ON bug.id = cus.bug_id
LEFT JOIN mantis_bug_history_table his ON bug.id = his.bug_id
WHERE bug.category_id = 1 AND
      (cus.field_id=1 OR cus.field_id IS NULL) AND      
      his.new_value = 80 AND 
      his.field_name = 'status' AND                 
      bug.id = 5171 AND
      cus.value='Sim'      
HAVING his.date_modified = MAX(his.date_modified)

Answer 2

A couple things. First, I don't think you can use aliases in the HAVING clause by default. I might be wrong, I'm having trouble parsing the documentation here. So the HAVING line should look more like `HAVING mantis_bug_history_table.date_modified = MAX(mantis_bug_history_table.date_modified)

I could be wrong though. That said, I think you're going to need to do a self join to get the MAX date_modified. Something like this:

select bug.id,
       bug.project_id,
       DATEDIFF (FROM_UNIXTIME(his.date_modified), FROM_UNIXTIME(date_submitted)) as dias_resolucao,
       DATE_FORMAT(FROM_UNIXTIME(his.date_modified), '%Y-%m') as ano_mes
from mantis_bug_table bug
left join mantis_project_table pro on bug.project_id = pro.id
left join mantis_custom_field_string_table cus on bug.id = cus.bug_id
left join mantis_bug_history_table his on bug.id = his.bug_id
inner join (select bug_id, max(date_modified) as max_date_modified from mantis_bug_history_table group by bug_id) as his_max_dates
 on his.bug_id = his_max_dates.bug_id and his.date_modified = his_max_dates.max_date_modified
where bug.category_id = 1 and
      (cus.field_id=1 or cus.field_id is null) and      
      his.new_value = 80 and 
      his.field_name = 'status' and                 
      bug.id = 5171 and
      cus.value='Sim'      

Give that a try.