Solved

Sum up Childs

Posted on 2013-01-28
4
139 Views
Last Modified: 2013-09-15
Im looking for advise on working summing together all the time spent on a particular job, however also including child jobs.

So currently I have a table with 3 coloums:-
JobNo (smallInt)
ParentJobNo (smallInt)
TimeSpend (smallInt)

Filled with some test data:-

JobNo      ParentJobNo      TimeSpent
10                  5
11      10            10
12      10            15
13      10            5
14      10            10
15      14            15
16      14            20
17      13            5
18                  10
19                  15
20      19            10

Currently we have the query:-
SELECT Jobs.JobNo, Jobs.TimeSpent
FROM Jobs
WHERE (((Jobs.ParentJobNo) Is Null));

Open in new window


Which gives:-
JobNo            TimeSpent
10            5
18            10
19            15

However what I would like it to do is sum all the child jobs, and child jobs in that, so the correct answer would be:-
JobNo      TimeSpent
10      85
18      10
19      25


My current idea is to create a function in PHP to look at each row, and look for child jobs and then children of that returning the number each time, but I would prefer to do this in the query itself.

I did think of creating a function in MySQL, but as the function would have to have use recursion, which is set to quite low on my shared server.

Im going to be using MySQL in the end, but using Access to quickly show my issue.

I hope someone can cope up with a better idea.
0
Comment
Question by:tonelm54
4 Comments
 
LVL 39

Expert Comment

by:als315
ID: 38827551
0
 
LVL 25

Expert Comment

by:Tomas Helgi Johannsson
ID: 38834890
Hi!

Try this

SELECT x.JobNo,SUM(x.TimeSpent) from(
SELECT b.ParentJobNo as JobNo, a.TimeSpent
FROM Jobs a, Jobs b
where a.JobNo = b.ParentJobNo
UNION ALL
SELECT c.ParentJobNo as JobNo, c.TimeSpent
FROM Jobs c
WHERE c.ParentJobNo Is Null))
)X
GROUP BY x.JobNo

Regards,
     Tomas Helgi
0
 

Author Comment

by:tonelm54
ID: 38884529
When I try I run the query:-
SELECT x.JobNo,SUM(x.TimeSpent) from(
SELECT b.ParentJobNo as JobNo, a.TimeSpent
FROM Jobs a, Jobs b
where a.JobNo = b.ParentJobNo
UNION ALL
SELECT c.ParentJobNo as JobNo, c.TimeSpent
FROM Jobs c
WHERE c.ParentJobNo Is Null))
)X
GROUP BY x.JobNo

Open in new window


MySQL says:-
Error Code: 1248. Every derived table must have its own alias      

If I do a quick dump on the database table, Ive got:-
CREATE TABLE `jobs` (
  `JobNo` int(11) NOT NULL,
  `ParentJobNo` int(11) DEFAULT NULL,
  `TimeSpent` int(11) DEFAULT NULL,
  PRIMARY KEY (`JobNo`)
);

INSERT INTO `jobs` VALUES (10,NULL,5),(11,10,10),(12,10,15),(13,10,5),(14,10,10)
,(15,14,15),(16,14,20),(17,13,5),(18,NULL,10),(19,NULL,15),(20,19,10);

Open in new window


Can you advise, the query seems to do what I want, but I cannot understand it to figure out how to debug it.
0
 
LVL 42

Accepted Solution

by:
Rob Jurd, EE MVE earned 500 total points
ID: 39448527
You need to specify an alias for the table and remove the erroneous brackets

SELECT x.JobNo,SUM(x.TimeSpent) from(
SELECT b.ParentJobNo as JobNo, a.TimeSpent
FROM Jobs a, Jobs b
where a.JobNo = b.ParentJobNo
UNION ALL
SELECT c.ParentJobNo as JobNo, c.TimeSpent
FROM Jobs c
WHERE c.ParentJobNo Is Null
) as x
GROUP BY x.JobNo

Open in new window

0

Featured Post

PRTG Network Monitor: Intuitive Network Monitoring

Network Monitoring is essential to ensure that computer systems and network devices are running. Use PRTG to monitor LANs, servers, websites, applications and devices, bandwidth, virtual environments, remote systems, IoT, and many more. PRTG is easy to set up & use.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Foreword In the years since this article was written, numerous hacking attacks have targeted password-protected web sites.  The storage of client passwords has become a subject of much discussion, some of it useful and some of it misguided.  Of cou…
As a database administrator, you may need to audit your table(s) to determine whether the data types are optimal for your real-world data needs.  This Article is intended to be a resource for such a task. Preface The other day, I was involved …
This Micro Tutorial will teach you how to censor certain areas of your screen. The example in this video will show a little boy's face being blurred. This will be demonstrated using Adobe Premiere Pro CS6.
This tutorial gives a high-level tour of the interface of Marketo (a marketing automation tool to help businesses track and engage prospective customers and drive them to purchase). You will see the main areas including Marketing Activities, Design …

770 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question