Nested SELECT Statement - sql

Question

SQL is not my forte, but I'm working on it - thank you for the replies.
I am working on a report that will return the completion percent of services for indiviudals in our contracts. There is a master table "Contracts," each individual Contract can have multiple services from the "services" table, each service has multiple standards for the "standards" table which records the percent complete for each standard.
I've gotten as far as calculating the total percent complete for each individual service for a specific Contract_ServiceID, but how do I return all the services percentages for all the contracts? Something like this:
Contract Service Percent complete
abc Company service 1 98%
abc Company service 2 100%
xyz Company service 1 50%
Here's what I have so far:
SELECT
Contract_ServiceId,
(SUM(CompletionPercentage)/COUNT(CompletionPercentage)) * 100 as "Percent Complete"
FROM dbo.Standard sta WITH (NOLOCK)
INNER JOIN dbo.Contract_Service conSer ON sta.ServiceId = conSer.ServiceId
LEFT OUTER JOIN dbo.StandardResponse standResp ON sta.StandardId = standResp.StandardId
AND conSer.StandardReportId = standResp.StandardReportId
WHERE Contract_ServiceId = '[an id]'
GROUP BY Contract_ServiceID
This gets me too:
Contract_serviceid Percent Complete
[an id] 100%
EDIT: Tables didn't show up in post.

Answer 1

I'm not sure if I understand the problem, if the result is ok for a service_contract you canContract Service
SELECT con.ContractId,
con.Contract,
conSer.Contract_ServiceID,
conSer.Service,
(SUM(CompletionPercentage)/COUNT(CompletionPercentage)) * 100 as "Percent Complete"
FROM dbo.Standard sta WITH (NOLOCK)
INNER JOIN dbo.Contract_Service conSer ON sta.ServiceId = conSer.ServiceId
INNER JOIN dbo.Contract con ON con.ContractId = conSer.ContractId
LEFT OUTER JOIN dbo.StandardResponse standResp ON sta.StandardId = standResp.StandardId
AND conSer.StandardReportId = standResp.StandardReportId
GROUP BY con.ContractId, con.Contract, conSer.Contract_ServiceID, conSer.Service
make sure you have all the columns you select from the Contract table in the group by clause

Answer 2

You should be able to add in your select the company name and group by that and the service id and ditch the where clause...
Perhaps like this:
SELECT
Contract,
Contract_ServiceId,
(SUM(CompletionPercentage)/COUNT(CompletionPercentage)) * 100 as "Percent Complete"
FROM dbo.Standard sta WITH (NOLOCK)
INNER JOIN dbo.Contract_Service conSer ON sta.ServiceId = conSer.ServiceId
LEFT OUTER JOIN dbo.StandardResponse standResp ON sta.StandardId = standResp.StandardId
AND conSer.StandardReportId = standResp.StandardReportId
GROUP BY Contract, Contract_ServiceID

Answer 3

Assuming your query works for just the one service, looks like you're most of the way there, leave off the WHERE clause to obtain all results, your GROUP BY will take care of one service per result.
Just join on the Contract table to show the contract related to each service, and you're done.

Answer 4

In addition to removing the where clause and adding more group conditions, you also will want to watch out for null records in each of your tables. This requires changing an INNER JOIN to a LEFT JOIN (unless you don't want to see those rows) and some ISNULL's to clean up data. I'm not sure where the StandardReportId concept falls in here, but it looks like a filtering mechanism that I won't toy with.
SELECT
ContractID
ISNULL(Contract_ServiceId, '-1') -- or some other stand in value
ISNULL((SUM(CompletionPercentage)/COUNT(CompletionPercentage)) * 100, 0) as "Percent Complete"
FROM
Contract AS con
LEFT OUTER JOIN dbo.Contract_Service conSer ON con.ContractID = conSer.ContractID
LEFT OUTER JOIN dbo.Standard sta WITH (NOLOCK) ON conSer.ServiceId = sta.StandardID
LEFT OUTER JOIN dbo.StandardResponse standResp ON sta.StandardId = standResp.StandardId
AND conSer.StandardReportId = standResp.StandardReportId
GROUP BY
ContractID, Contract_ServiceID

Answer 5

Because you are grouping by the contract serviceid I think you can just remove the where clause and it should calculate the percentage for all contact serviceids.
If there are no records in dbo.Standard for that contract serviceid, you may need to left outer join instead from the contract service table to the dbo.Standard table in order to show contracts without completion records.
I hope that makes sense... My SQL is getting rusty after migrating to a data framework.

Answer 6

(SUM(CompletionPercentage)/COUNT(CompletionPercentage)) * 100
If CompletionPercentage is an int field you will have trouble with integer math. Anytime you divide by an integer you need to multiply it by 1.0 to make sure it is considering the number as a decimal. Otherwise 49/100 would = 0.