Optimizing a Stored Procedure - sql

Question

I have a massive query that has been working just fine, however, due to the number or records now in my database, the query is taking longer and longer for the stored procedure to complete.
I had a hard enough time getting the query to work in the first place and I'm not confident in myself to either A) Simplify the query or B) break it into smaller queries/stored procedures.
Can any expert help me out?
SELECT
r.resourceFirstName,
r.resourceLastName,
a.eventDateTime,
CONVERT(char(1), a.eventType) as eventType,
CONVERT(varchar(5), a.reasonCode) as reasonCode,
r.extension,
GETDATE() AS ciscoDate into #temp_Agent
FROM
CCX1.db_cra.dbo.Resource r
INNER JOIN CCX1.db_cra.dbo.AgentStateDetail a
ON r.resourceID = a.agentID
INNER JOIN (
SELECT
p.resourceFirstName,
p.resourceLastName,
MAX(e.eventDateTime) MaxeventDateTime
FROM
CCX1.db_cra.dbo.Resource p
INNER JOIN CCX1.db_cra.dbo.AgentStateDetail e
ON p.resourceID = e.agentID
where
e.eventDateTime > (GETDATE() - 1)
GROUP BY
p.resourceFirstName,
p.resourceLastName
) d
ON r.resourceFirstName = d.resourceFirstName
AND r.resourceLastName = d.resourceLastName
AND a.eventDateTime = d.MaxeventDateTime
AND r.active = 1
where
a.eventDateTime >= (GETDATE() - 7)
ORDER BY
r.resourceLastName,
r.resourceFirstName ASC

Answer 1

Can't give the correct answer having only the query. But...
Consider putting an index on "eventDateTime".
It appears you are joining with a set of records within 1 day. That would make the 7 day filter in the outer query irrelevant. I don't have the ability to test, but maybe your query can be reduced to this? (pseudo code below)
Also consider different solutions. Maybe partition a table based on the datetime. Maybe have a separate database for reporting using star schemas or cube design.
What is being done with the temporary table #temp_Agent?
declare #max datetime = (select max(eventDateTime)
from CCX1.db_cra.dbo.AgentStateDetail
where active=1
and eventDateTime > getdate()-1);
if(#max is null)
exit no records today
SELECT r.resourceFirstName,
r.resourceLastName,
a.eventDateTime,
CONVERT(char(1), a.eventType) as eventType,
CONVERT(varchar(5), a.reasonCode) as reasonCode,
r.extension,
GETDATE() AS ciscoDate
into #temp_Agent
FROM CCX1.db_cra.dbo.Resource r
INNER JOIN CCX1.db_cra.dbo.AgentStateDetail a ON r.resourceID = a.agentID
where r.active = 1
and a.eventDateTime = #max;

Answer 2

Without the full definition of your tables it is hard to troubleshoot why the query is hanging out, but i give you a couple of tips that could help you improve the performance in the Query:
Instead of using a temporary table such as "#temp_Agent" it is preferable to create a local Variable of type "Table". You can achieve exactly the same result but you can drastically increase the performace because:
A local variable of the type "Table" can be created with primary keys and indexes, which improves how SQL finds the information.
A local variable can be clustered, which also improves the performacne in certain scenarios, because the information is accesed directly from disk
A temporary table requires that SQL resolves at runtime the types of columns that should be used to store the information obtained by the query.
If you require to store information in temporary tables, variables, etc, avoid storing unnecesary information in those variables. for example, if you only require latter in your proccess two id colums, then avoid including extra columns that you can retrieve lather
If there is a bunch of information that you need to retireve from multiple sources, you should consider using a view, which also can be indexed and improve the retrieval of the information.
Avoid using unnecesary sorting, grouping, conversions and joins of strings. These particular operations cad degrade drastically the performance of a QUery.
As an extra tip, you can made use of the SQL server tools designed to improve your database and objects:
Check the execution plan of your query (Menu Query->Include Actual Execution Plan, or control + M)
Run the SQL Server Engine Tunning Advisor to analyze a trace file(See SQL Server Profiler) and add extra indexes to improve the database performace
Check with SQL Server Profiler if your Queryes are not generating Deadlocks in the tables you are using to get the information. It is a good practice to use "Hints" in all of your queries to avoid lock problems and other behaviors that in certain scenarios you want to avoid.
Se attached links to better understand what i mean:
Understanding Execution Plan
Usage of Hints
Tunning Options available in SQL Server
I hope the information helps.

Answer 3

Assuming this is SQLServer, try:
WITH CTE AS
(SELECT r.resourceFirstName,
r.resourceLastName,
a.eventDateTime,
CONVERT(char(1), a.eventType) as eventType,
CONVERT(varchar(5), a.reasonCode) as reasonCode,
r.extension,
GETDATE() AS ciscoDate,
RANK() OVER (PARTITION BY r.resourceFirstName, r.resourceLastName
ORDER BY a.eventDateTime DESC) RN
FROM CCX1.db_cra.dbo.Resource r
INNER JOIN CCX1.db_cra.dbo.AgentStateDetail a
ON r.resourceID = a.agentID AND a.eventDateTime >= (GETDATE() - 1)
where r.active = 1)
SELECT resourceFirstName, resourceLastName, eventDateTime, eventType, reasonCode, r.extension, ciscoDate
into #temp_Agent
FROM CTE
WHERE RN=1
ORDER BY r.resourceLastName, r.resourceFirstName ASC