Query performance to be increased..please help..

Question

hi,
SELECT TSK.TaskID AS [SprintID]
,TSK.Title AS [Sprint]
,TSK.[StartDate]
,TSK.[EndDate]
,SRA.[ResourceID]
,R.[ResourceName]
,D.[UID] AS [DivisionID]
,D.[Division]
,T.[UID] AS [TechnologyID]
,T.Technology
,'Free On '+ CONVERT(NVARCHAR,TSK.[EndDate],103) [FreeStatus]
,ISNULL(RSS.[Rating],0) [Rating]
FROM tb_Technology T
,Tasks TSK INNER JOIN TasksResource SRA ON TSK.TaskID = SRA.TaskID
INNER JOIN tb_Resource R ON R.[UID] = SRA.[ResourceID] AND R.IsActive = 1
LEFT JOIN tb_ResourceSkillset RSS ON RSS.[ResourceID] = R.[UID] AND RSS.IsActive =1
LEFT JOIN tb_Division D ON D.[UID] = R.[DivisionID]
WHERE TSK.EndDate >= @StartDate AND TSK.EndDate <= @EndDate AND D.IsActive = 1 AND T.IsActive = 1
AND D.[UID] = (CASE WHEN @DivisionID > 0 THEN @DivisionID ELSE D.[UID] END)
AND T.[UID] = (CASE WHEN @TechnologyID > 0 THEN @TechnologyID ELSE T.[UID] END)
UNION
SELECT 0 AS [SprintID]
,'' AS [Sprint]
,CAST(GETDATE() AS DATE) AS [StartDate]
,CAST(GETDATE() AS DATE) AS [EndDate]
,R.[UID] AS [ResourceID]
,R.[ResourceName]
,D.[UID] AS [DivisionID]
,D.[Division]
,T.[UID] AS [TechnologyID]
,T.Technology
,'Free' [FreeStatus]
,ISNULL(RSS.[Rating],0) [Rating]
FROM tb_Technology T,
tb_Resource R
LEFT JOIN tb_ResourceSkillset RSS ON RSS.[ResourceID] = R.[UID] AND RSS.IsActive = 1
LEFT JOIN tb_Division D ON D.[UID] = R.[DivisionID]
WHERE R.[UID] NOT IN (SELECT SRA.ResourceID FROM TasksResource SRA)
AND R.IsActive = 1 AND T.IsActive = 1
AND D.[UID] = (CASE WHEN @DivisionID > 0 THEN @DivisionID ELSE D.[UID] END)
AND T.[UID] = (CASE WHEN @TechnologyID > 0 THEN @TechnologyID ELSE T.[UID] END)
i'm using the above code..where my technology table has 18,900 rows and task has 109 rows.
when these 2 are cross joined i think more time taking...this query is taking much time to execute.pls help me how can i retrieve the result with less time.
total result is 3lakhs rows and running more than 7-8min..
lucky

Answer 1

Hallo Lucky,
additional to the points of Erland and Uri some questions:
How do you pass the variables to the query?
DECLARE @StartDate date;
DECLARE @EndDate date;
DECLARE @DivisionId int;
SET @StartDate = '20130101';
SET @EndDate = '20130131';
SET @DivisionId = 1;
SELECT ....
ALL stuff from your query;
or is it part of a procedure where these parameters are coming from the proc itself?
The reason is a quite simple one.
If you run the query inside SSMS with my given example the query optimizer doesn't know the values in the moment of compilation and estimates only 1 record.
Please share the execution plan with us to help you.
Use your query with the following statement before it:
SET STATISTICS PROFILE ON;
GO
SELECT
ALL FROM your query
Can you post the result (in a readable Format please!) here?
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