Is there a way to get the amount of 'selects' from a mssql table?
I mean without rewriting application to log every request or without parsing sql profile logs...
Is there any build-in tool (sql request)?
SQL Server maintains index usage statistics since last restart. You can use user_reads column from query bellow to get wanted statistics:
SELECT OBJECT_NAME(ddius.[object_id], ddius.database_id) AS [object_name] ,
ddius.index_id ,
ddius.user_seeks ,
ddius.user_scans ,
ddius.user_lookups ,
ddius.user_seeks + ddius.user_scans + ddius.user_lookups
AS user_reads ,
ddius.user_updates AS user_writes ,
ddius.last_user_scan ,
ddius.last_user_update
FROM sys.dm_db_index_usage_stats ddius
WHERE ddius.database_id > 4 -- filter out system tables
AND OBJECTPROPERTY(ddius.OBJECT_ID, 'IsUserTable') = 1
AND ddius.index_id > 0 -- filter out heaps
AND database_id = DB_ID()
ORDER BY user_reads DESC
Hey guys the code below is taking a really long time. I've been looking at it for quite a while. Is there anything that stands out as the obvious cause of delay?
[SQLSRV-3-JB] is a linked server BTW
Select count(cast (Unique_ID as bigint)) as [Count],
T.[Region_Code],
T.[Region_Name],
U.[Region_Code],
Y.[Examination_Year],
case when [Subject] = 'MUSIC THEORY' THEN 'Theory'
else 'Practical'
end
from [SQLSRV-3-JB].[X].[dbo].[Exam_and_Candidate_Details] Y
left join [SQLSRV-3-JB].[X].[dbo].[UK_Exam_Centre_Info] T
on Y.Centre_Code = T.Centre_Code
left join [SQLSRV-3-JB].[X].[dbo].[UK_Exam_Centres] U
on Y.Centre_Code = U.Centre_Code
where Y.[Examination_Year] between 2010 and 2016
group by Y.[Examination_Year],
T.[Region_Code],
T.[Region_Name],
U.[Region_Code],
case when [Subject] = 'MUSIC THEORY' THEN 'Theory'
else 'Practical'
end
Yes, there is one very obvious problem - the remote server. When you use a linked server like this, SQL Server has a disturbing habit of pulling all of the data in the remote tables to the local server before performing JOINs or filtration.
The correct way to handle this is to make this query a view on the remote server, and query the view with your WHERE clause on your end. So, your remote code would look like this:
-- Remote Server
USE X
GO
CREATE VIEW dbo.ExamCenterInfo
AS
Select count(cast (Unique_ID as bigint)) as [Count],
T.[Region_Code],
T.[Region_Name],
U.[Region_Code],
Y.[Examination_Year],
case when [Subject] = 'MUSIC THEORY' THEN 'Theory'
else 'Practical'
end
from dbo.[Exam_and_Candidate_Details] Y
left join dbo.[UK_Exam_Centre_Info] T
on Y.Centre_Code = T.Centre_Code
left join dbo.[UK_Exam_Centres] U
on Y.Centre_Code = U.Centre_Code
group by Y.[Examination_Year],
T.[Region_Code],
T.[Region_Name],
U.[Region_Code],
case when [Subject] = 'MUSIC THEORY' THEN 'Theory'
else 'Practical'
end
Then your local code:
-- Local Server
SELECT *
FROM [SQLSRV-3-JB].[X].[dbo].ExamCenterInfo ECI
where ECI.[Examination_Year] between 2010 and 2016
NOTE: There is some possibility that this will pull all of the view output before filtering by year. If this is still a problem, you will have to create a more complex mechanism to execute the view with filtration on the remote server.
We're running a web app (2 instances) on Azure, backed by a SQL Azure database. At any given time there are 50-150 users using the website. The database runs at S2 performance level. The DTU is around 20% on average.
However, a few times every day I suddenly get hundreds of errors in my logs with timeouts, like this:
An error occurred while executing the command definition. See the inner exception for details.
The wait operation timed out.
Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding. This failure occurred while attempting to connect to the routing destination. The duration spent while attempting to connect to the original server was - [Pre-Login] initialization=1; handshake=21; [Login] initialization=0; authentication=0; [Post-Login] complete=1;
We're using EF6 for queries with the default command timeout. I've configured this execution strategy:
SetExecutionStrategy("System.Data.SqlClient",
() => new SqlAzureExecutionStrategy(10, TimeSpan.FromSeconds(15)));
The database (about 15GB total) is heavily indexed. These errors occur all over the place, usually dozens to hundreds within 1-2 minutes.
What steps can I take to prevent this from happening?
The fact that it happens in 1-2 minutes might mean a burst in activity or some process that might be locking up tables.
If your DTU during those times is at 20% is not a CPU issue, but you can always find which are the bottlenecks by running this query on the DB:
SELECT TOP 10
total_worker_time/execution_count AS Avg_CPU_Time
,execution_count
,total_elapsed_time/execution_count as AVG_Run_Time
,(SELECT
SUBSTRING(text,statement_start_offset/2,(CASE
WHEN statement_end_offset = -1 THEN LEN(CONVERT(nvarchar(max), text)) * 2
ELSE statement_end_offset
END -statement_start_offset)/2
) FROM sys.dm_exec_sql_text(sql_handle)
) AS query_text
FROM sys.dm_exec_query_stats
ORDER BY Avg_CPU_Time DESC
Even if the DB is heavily indexed, indexes get fragmented, I'd advice running this to check the current fragmentation:
select a.*,b.AverageFragmentation from
( SELECT tbl.name AS [Table_Name], tbl.object_id, i.name AS [Name], i.index_id, CAST(CASE i.index_id WHEN 1 THEN 1 ELSE 0 END AS bit) AS [IsClustered],
CAST(case when i.type=3 then 1 else 0 end AS bit) AS [IsXmlIndex], CAST(case when i.type=4 then 1 else 0 end AS bit) AS [IsSpatialIndex]
FROM
sys.tables AS tbl
INNER JOIN sys.indexes AS i ON (i.index_id > 0 and i.is_hypothetical = 0) AND (i.object_id=tbl.object_id))a
inner join
( SELECT tbl.object_id, i.index_id, fi.avg_fragmentation_in_percent AS [AverageFragmentation]
FROM
sys.tables AS tbl
INNER JOIN sys.indexes AS i ON (i.index_id > 0 and i.is_hypothetical = 0) AND (i.object_id=tbl.object_id)
INNER JOIN sys.dm_db_index_physical_stats(DB_ID(), NULL, NULL, NULL, 'LIMITED') AS fi ON fi.object_id=CAST(i.object_id AS int) AND fi.index_id=CAST(i.index_id AS int)
)b
on a.object_id=b.object_id and a.index_id=b.index_id
order by AverageFragmentation desc
You can also use Azure Automation to schedule an automatic rebuilding of fragmented indexes, see answer at: Why my Azure SQL Database indexes are still fragmented?
This is running on SQL Server 2000
Background: when a new server is brought onto the network, it will pass through a series of status (stages) such as (loading, testing, configuring, production, etc) were production is the final step (not every server in the report will be in production so this bit of information may be a moot point).
I inherited this so if there are any questions, I'll answer them as best as I can. I'm trying to run a query to get the latest status of all the servers during a specific time frame. My query is currently returning every status for the server and I only need the current status and that is where I need your help.
The query I'm working with is as follows:
SELECT SD.ProjectName, SD.SystemName, SD.Status, H.history_id
FROM dbo.SI_SystemDetail AS SD
INNER JOIN dbo.SI_Projects AS P ON SD.ProjectName = P.ProjectName
INNER JOIN dbo.SI_StatusHistory AS H ON SD.SystemName = H.SystemName
WHERE
(P.Cancelled = 'N')
AND (P.Platform LIKE '%ibm%')
AND ('20110101' <= CONVERT(varchar(8), H.EffectiveDate, 112))
AND (CONVERT(varchar(8), H.EffectiveDate, 112) <= '20111111')
ORDER BY
H.history_id DESC, SD.SystemName, SD.ContactSBCuid, SD.ActualLiveDAte DESC,
SD.ProjectName, SD.SystemType, H.EffectiveDate`
This will return several duplicates for systemname but I only need one and that should correspond with the highest history_id number. For example, lets say there is a server named:
Server Name Status History_ID
Server01 Loading 1001
Server01 Configuring 1081
Server01 Testing 1101
Server01 Production 1451
Server02 Loading 1002
Server02 Configuring 1083
Server02 Testing 1104
Server02 Failed 1455
I would just need the following results returned:
Server Name Status History_ID
Server01 Production 1451
Server02 Failed 1455
Thanks in advance for the assistance.
UNTESTED:
SELECT SD.ProjectName, SD.SystemName, SD.Status, H.history_id
FROM dbo.SI_SystemDetail AS SD
INNER JOIN dbo.SI_Projects AS P
ON SD.ProjectName = P.ProjectName
INNER JOIN dbo.SI_StatusHistory AS H
ON SD.SystemName = H.SystemName
WHERE (P.Cancelled = 'N') AND (P.Platform LIKE '%ibm%') AND ('20110101' <= CONVERT(varchar(8), H.EffectiveDate, 112)) AND (CONVERT(varchar(8), H.EffectiveDate, 112) <= '20111111')
AND history_ID = (
Select max(history_ID)
FROM SI_Status_History iSH
where iSH.SystemName = SD.SystemName)
ORDER BY H.history_id DESC, SD.SystemName, SD.ContactSBCuid, SD.ActualLiveDAte DESC, SD.ProjectName, SD.SystemType, H.EffectiveDate
Is there a way to list the queries that are currently running on MS SQL Server (either through the Enterprise Manager or SQL) and/or who's connected?
I think I've got a very long running query is being execute on one of my database servers and I'd like to track it down and stop it (or the person who keeps starting it).
This will show you the longest running SPIDs on a SQL 2000 or SQL 2005 server:
select
P.spid
, right(convert(varchar,
dateadd(ms, datediff(ms, P.last_batch, getdate()), '1900-01-01'),
121), 12) as 'batch_duration'
, P.program_name
, P.hostname
, P.loginame
from master.dbo.sysprocesses P
where P.spid > 50
and P.status not in ('background', 'sleeping')
and P.cmd not in ('AWAITING COMMAND'
,'MIRROR HANDLER'
,'LAZY WRITER'
,'CHECKPOINT SLEEP'
,'RA MANAGER')
order by batch_duration desc
If you need to see the SQL running for a given spid from the results, use something like this:
declare
#spid int
, #stmt_start int
, #stmt_end int
, #sql_handle binary(20)
set #spid = XXX -- Fill this in
select top 1
#sql_handle = sql_handle
, #stmt_start = case stmt_start when 0 then 0 else stmt_start / 2 end
, #stmt_end = case stmt_end when -1 then -1 else stmt_end / 2 end
from sys.sysprocesses
where spid = #spid
order by ecid
SELECT
SUBSTRING( text,
COALESCE(NULLIF(#stmt_start, 0), 1),
CASE #stmt_end
WHEN -1
THEN DATALENGTH(text)
ELSE
(#stmt_end - #stmt_start)
END
)
FROM ::fn_get_sql(#sql_handle)
If you're running SQL Server 2005 or 2008, you could use the DMV's to find this...
SELECT *
FROM sys.dm_exec_requests
CROSS APPLY sys.dm_exec_sql_text(sql_handle)
More about sys.dm_exec_requests
More about sys.dm_exec_sql_text
You can run the sp_who command to get a list of all the current users, sessions and processes. You can then run the KILL command on any spid that is blocking others.
I would suggest querying the sys views. something similar to
SELECT *
FROM
sys.dm_exec_sessions s
LEFT JOIN sys.dm_exec_connections c
ON s.session_id = c.session_id
LEFT JOIN sys.dm_db_task_space_usage tsu
ON tsu.session_id = s.session_id
LEFT JOIN sys.dm_os_tasks t
ON t.session_id = tsu.session_id
AND t.request_id = tsu.request_id
LEFT JOIN sys.dm_exec_requests r
ON r.session_id = tsu.session_id
AND r.request_id = tsu.request_id
OUTER APPLY sys.dm_exec_sql_text(r.sql_handle) TSQL
This way you can get a TotalPagesAllocated which can help you figure out the spid that is taking all the server resources. There has lots of times when I can't even bring up activity monitor and use these sys views to see what's going on.
I would recommend you reading the following article. I got this reference from here.
As a note, the SQL Server Activity Monitor for SQL Server 2008 can be found by right clicking your current server and going to "Activity Monitor" in the context menu. I found this was easiest way to kill processes if you are using the SQL Server Management Studio.
There are various management views built into the product. On SQL 2000 you'd use sysprocesses. On SQL 2K5 there are more views like sys.dm_exec_connections, sys.dm_exec_sessions and sys.dm_exec_requests.
There are also procedures like sp_who that leverage these views. In 2K5 Management Studio you also get Activity Monitor.
And last but not least there are community contributed scripts like the Who Is Active by Adam Machanic.
SELECT
p.spid, p.status, p.hostname, p.loginame, p.cpu, r.start_time, r.command,
p.program_name, text
FROM
sys.dm_exec_requests AS r,
master.dbo.sysprocesses AS p
CROSS APPLY sys.dm_exec_sql_text(p.sql_handle)
WHERE
p.status NOT IN ('sleeping', 'background')
AND r.session_id = p.spid
Actually, running EXEC sp_who2 in Query Analyzer / Management Studio gives more info than sp_who.
Beyond that you could set up SQL Profiler to watch all of the in and out traffic to the server. Profiler also let you narrow down exactly what you are watching for.
For SQL Server 2008:
START - All Programs - Microsoft SQL Server 2008 - Performance Tools - SQL Server Profiler
Keep in mind that the profiler is truly a logging and watching app. It will continue to log and watch as long as it is running. It could fill up text files or databases or hard drives, so be careful what you have it watch and for how long.
In the Object Explorer, drill-down to: Server -> Management -> Activity Monitor. This will allow you to see all connections on to the current server.
You can use below query to find running last request:
SELECT
der.session_id
,est.TEXT AS QueryText
,der.status
,der.blocking_session_id
,der.cpu_time
,der.total_elapsed_time
FROM sys.dm_exec_requests AS der
CROSS APPLY sys.dm_exec_sql_text(sql_handle) AS est
Using below script you can also find number of connection per database:
SELECT
DB_NAME(DBID) AS DataBaseName
,COUNT(DBID) AS NumberOfConnections
,LogiName
FROM sys.sysprocesses
WHERE DBID > 0
GROUP BY DBID, LogiName
For more details please visit:
http://www.dbrnd.com/2015/06/script-to-find-running-process-session-logged-user-in-sql-server/
here is a query that will show any queries that are blocking. I am not entirely sure if it will just show slow queries:
SELECT p.spid
,convert(char(12), d.name) db_name
, program_name
, convert(char(12), l.name) login_name
, convert(char(12), hostname) hostname
, cmd
, p.status
, p.blocked
, login_time
, last_batch
, p.spid
FROM master..sysprocesses p
JOIN master..sysdatabases d ON p.dbid = d.dbid
JOIN master..syslogins l ON p.sid = l.sid
WHERE p.blocked = 0
AND EXISTS ( SELECT 1
FROM master..sysprocesses p2
WHERE p2.blocked = p.spid )
The right script would be like this:
select
p.spid, p.status,p.hostname,p.loginame,p.cpu,r.start_time, t.text
from sys.dm_exec_requests as r, sys.sysprocesses p
cross apply sys.dm_exec_sql_text(p.sql_handle) t
where p.status not in ('sleeping', 'background')
and r.session_id=p.spid
SELECT
p.spid, p.status, p.hostname, p.loginame, p.cpu, r.start_time, t.text
FROM
sys.dm_exec_requests as r,
master.dbo.sysprocesses as p
CROSS APPLY sys.dm_exec_sql_text(p.sql_handle) t
WHERE
p.status NOT IN ('sleeping', 'background')
AND r.session_id = p.spid
And
KILL #spid
in 2005 you can right click on a database, go to reports and there's a whole list of reports on transitions and locks etc...
Trying to put things together (hope to be helpful):
SELECT
p.spid,
RIGHT(CONVERT(varchar, DATEADD(ms, DATEDIFF(ms, p.last_batch, GETDATE()), '1900-01-01'), 121), 12) AS [batch_duration],
p.[program_name],
p.hostname,
MAX(p.loginame) AS loginame,
(SELECT SUBSTRING(text, COALESCE(NULLIF(spid.stmt_start, 0), 1) + 1, CASE spid.stmt_end WHEN -1 THEN DATALENGTH(text) ELSE (spid.stmt_end - spid.stmt_start) END) FROM ::fn_get_sql(spid.[sql_handle])) AS [sql]
FROM
master.dbo.sysprocesses p
LEFT JOIN (
SELECT
ROW_NUMBER() OVER(PARTITION BY spid ORDER BY ecid) AS i,
spid,
[sql_handle],
CASE stmt_start WHEN 0 THEN 0 ELSE stmt_start / 2 END AS stmt_start,
CASE stmt_end WHEN -1 THEN -1 ELSE stmt_end / 2 END AS stmt_end
FROM sys.sysprocesses
) spid ON p.spid = spid.spid AND spid.i = 1
WHERE
p.spid > 50
AND p.status NOT IN ('background', 'sleeping')
AND p.cmd NOT IN ('AWAITING COMMAND', 'MIRROR HANDLER', 'LAZY WRITER', 'CHECKPOINT SLEEP', 'RA MANAGER')
GROUP BY
p.spid,
p.last_batch,
p.[program_name],
p.hostname,
spid.stmt_start,
spid.stmt_end,
spid.[sql_handle]
ORDER BY
batch_duration DESC,
p.spid
;
Use Sql Server Profiler (tools menu) to monitor executing queries and use activity monitor in Management studio to see how is connected and if their connection is blocking other connections.
You should try very usefull procedure sp_whoIsActive which can be found here: http://whoisactive.com and it is free.