Inefficient SQL query with joined tables - sql-server

Question

I have a table with 1700 rows of data. I'm querying it using the query below which pulls complimentary data from related tables too. It's currently running very slowly (around 10 seconds).
How can I improve the efficiency of this query?
SELECT [jobID] ,
(SELECT orgname
FROM pm_clients c
WHERE c.orgID IN
(SELECT orgid
FROM pm_jobs j
WHERE j.jobid=t.jobid
AND j.jobStatus>=13)) AS orgname ,
(SELECT sector
FROM pm_clients c
WHERE c.orgID IN
(SELECT orgid
FROM pm_jobs j
WHERE j.jobid=t.jobid
AND j.jobStatus>=13)) AS sector ,
(SELECT region= CASE country
WHEN 1 THEN region
ELSE
(SELECT countryname
FROM AT_A_CountryCodes x
WHERE x.id= l.country)
END
FROM PM_ClientDetails l
WHERE l.userid =
(SELECT userid
FROM pm_jobs j
WHERE j.jobid=t.jobid)) AS region ,
(SELECT postcode
FROM PM_ClientDetails l
WHERE l.userid =
(SELECT userid
FROM pm_jobs j
WHERE j.jobid=t.jobid)) AS postcode ,
(SELECT firstname
FROM users u
WHERE u.userid =
(SELECT pmid
FROM pm_jobs j
WHERE j.jobid=t.jobid)) AS PM ,
[creationDate] ,
(SELECT statusName
FROM pm_jobstatus j
WHERE j.[statusID]=t.jobStatus) AS JobStatus ,
[completionDate] ,
[deadline],
[jobTitle] ,
(SELECT currencysymbol
FROM at_a_currency c
WHERE c.currencyID =
(SELECT top(1) quoteCurrency
FROM PM_Quotes q
WHERE q.taskid IN
(SELECT taskid
FROM pm_tasks x
WHERE x.jobID=t.jobid))) AS currency ,
(SELECT sum(quoteSubTotal)
FROM PM_Quotes q
WHERE q.taskid IN
(SELECT taskid
FROM pm_tasks x
WHERE x.jobID=t.jobid)) AS subtotal ,
(SELECT sum(quoteVAT)
FROM PM_Quotes q
WHERE q.taskid IN
(SELECT taskid
FROM pm_tasks x
WHERE x.jobID=t.jobid)) AS VAT ,
(SELECT sum(quoteTotal)
FROM PM_Quotes q
WHERE q.taskid IN
(SELECT taskid
FROM pm_tasks x
WHERE x.jobID=t.jobid)) AS total ,
(SELECT [purchaseOrder]
FROM pm_jobs j
WHERE j.jobid=t.jobid) AS purchaseOrder ,
(SELECT [clientReference]
FROM pm_jobs j
WHERE j.jobid=t.jobid) AS clientReference ,
(SELECT CASE
WHEN [deadline]='1900-01-01 00:00:00' THEN 1
WHEN [completiondate]>dateadd(dd,1,[deadline]) THEN 0
WHEN [completiondate]<=dateadd(dd,1,[deadline])THEN 1
WHEN [completiondate] IS NULL THEN 0
END) AS completedOnTime
FROM [PM_jobs] t
WHERE jobStatus>=13
Edit
Thanks to #GuidoG for the response. Here's the amended query which is much faster now.
SELECT j.jobid,
c.orgname,
c.sector,
(SELECT region= CASE country
WHEN 1 THEN region
ELSE (SELECT countryname
FROM at_a_countrycodes x
WHERE x.id = l.country)
END) AS region,
l.postcode,
(SELECT firstname
FROM users u
WHERE u.userid = J.pmid) AS PM,
j.creationdate,
(SELECT statusname
FROM pm_jobstatus x
WHERE x.[statusid] = j.jobstatus) AS JobStatus,
j.[completiondate],
j.[deadline],
j.[jobtitle],
j.purchaseorder,
j.clientreference,
(SELECT currencysymbol
FROM at_a_currency c
WHERE c.currencyid = l.clientcurrency) AS currency,
Sum(q.quotesubtotal) AS subtotal,
Sum(q.quotevat) AS VAT,
Sum(q.quotetotal) AS total,
(SELECT CASE
WHEN j.[deadline] = '1900-01-01 00:00:00' THEN 1
WHEN j.[completiondate] > Dateadd(dd, 1, j.[deadline]) THEN 0
WHEN j.[completiondate] <= Dateadd(dd, 1, j.[deadline])THEN 1
WHEN j.[completiondate] IS NULL THEN 0
END) AS completedOnTime,
Count(t.taskid) AS taskcount
FROM [pm_jobs] j
INNER JOIN pm_clients c
ON j.orgid = c.orgid
INNER JOIN pm_clientdetails l
ON j.userid = l.userid
INNER JOIN pm_tasks t
ON j.jobid = t.jobid
INNER JOIN pm_quotes q
ON q.taskid = t.taskid
AND t.jobid = j.jobid
WHERE jobstatus >= 13
GROUP BY j.jobid,
c.orgname,
c.sector,
l.country,
l.region,
l.postcode,
l.firstname,
j.creationdate,
j.jobstatus,
j.completiondate,
j.deadline,
j.jobtitle,
j.purchaseorder,
j.clientreference,
l.clientcurrency,
J.pmid
ORDER BY completiondate DESC

Answer 1

You should consider joining instead of subquerying. Here is a small example to get you on your way:
SELECT t.jobID ,
c.orgName,
c.sector
FROM [SQL2012_921487_atlas].[dbo].[PM_jobs] t
inner join pm_clients c on t.orgID = c.orgID
WHERE jobStatus>=13
When subquerying like you did, you force SQL Server to read table pm_clients several times; joining enables it to read pm_clients only 1 time.