Thursday, March 19, 2015

Logging the performance counter

The following script creates a table PerfMondata in a SQLMonitor database and logs the counter in the interval of 30 seconds



use [SQLMonitor]



GO
 
SET NOCOUNT ON ;

DECLARE @PerfCounters TABLE (

[Counter] nvarchar(770),

[CounterType] int,

[FirstValue] decimal (38,2),

[FirstDateTime] datetime,

[SecondValue] decimal(38,2),

[SecondDateTime] datetime ,

[ValueDiff] AS ([SecondValue] - [FirstValue]) ,

[timeDiff] AS (DateDiff(ss,[FirstDateTime],[SecondDateTime])),

[CounterValue] decimal(38,2)

) ;




 
INSERT INTO @PerfCounters (

[Counter],

[CounterType],

[FirstValue],


[FirstDateTime]
)
 
SELECT RTRIM([OBJECT_NAME]) + N' : ' + RTRIM([counter_name]) + N':' +RTRIM([instance_name]),[cntr_type],[cntr_value],GETDATE()

from sys.dm_os_performance_counters

WHERE [counter_name] IN ('Page life expectancy','Lazy writes/sec', 'Page reads/sec', 'Page writes/sec ','Page lookups/sec',

'Free list stalls/sec','User Connections','Lock Waits/sec','Number of Deadlocks/sec',

'Transactions/sec ', 'Forwarded Records/sec','Index Searches/sec','Batch Requests/sec','SQL Compilations/sec','SQL Re-Compilations/sec',

'Target Server Memory (KB)', 'Latch Waits/sec' ,'Buffer cache hit ratio'



)
 
order by [OBJECT_NAME] + N' : ' + [counter_name]+ N':' +RTRIM([instance_name])



 
 
Waitfor delay '00:00:30';


Update @PerfCounters

SET [SecondValue]= [cntr_value],

[SecondDateTime] = GETDATE()

from sys.dm_os_performance_counters

where [Counter] = RTRIM([OBJECT_NAME]) + N' : ' + RTRIM([counter_name]) + N':' +RTRIM([instance_name])

AND [counter_name] IN ('Page life expectancy','Lazy writes/sec', 'Page reads/sec', 'Page writes/sec ','Page lookups/sec',

'Free list stalls/sec','User Connections','Lock Waits/sec','Number of Deadlocks/sec',

'Transactions/sec ', 'Forwarded Records/sec','Index Searches/sec','Batch Requests/sec','SQL Compilations/sec','SQL Re-Compilations/sec',

'Target Server Memory (KB)', 'Latch Waits/sec','Buffer cache hit ratio' )


 

--for per sec counters

Update @PerfCounters

SET CounterValue = ([SecondValue]-[FirstValue])/(DateDiff(ss,[FirstDateTime],[SecondDateTime]))

where [counterType] = 272696576;


--for non per sec counters

 
Update @PerfCounters

SET CounterValue = [SecondValue]

where [counterType] <> 272696576;

select * from @PerfCounters



INSERT INTO PerfMondata (perfCounter,Value,CAptureDate)

SELECT [counter],[CounterValue],[SecondDateTime] from @PerfCounters



--select * from PerfMondata




--following stored procedure takes in a counter as the parameter and displays the report on a specific counter

use [SQLMonitor]



GO

 


if OBJECTPROPERTY(OBJECT_ID('proc_sqlAdmin_PerfMonReport'),'IsProcedure')= 1

DROP PROCEDURE proc_sqlAdmin_PerfMonReport

GO





CREATE PROCEDURE dbo.proc_sqlAdmin_PerfMonReport

(



@Counter nvarchar(128)= '%'

)



AS



BEGIN ;

SELECT [Perfcounter],value,captureDate

from perfMondata

WHERE [Perfcounter] like @Counter

ORDER BY [Perfcounter],[captureDate]



END ;



/*



exec dbo.proc_sqlAdmin_PerfMonReport '%Page life expectancy%'

exec dbo.proc_sqlAdmin_PerfMonReport '%Batch Requests/sec%'

exec dbo.proc_sqlAdmin_PerfMonReport '%Page Writes/sec%'

*/
 




 

Thursday, March 12, 2015

Dynamic sql : Getting result of dynamic SQL into a variable

DECLARE @sqlCommand nvarchar(1000)
DECLARE @city varchar(75)
declare @counts int
SET @city = 'New York'
SET @sqlCommand = 'SELECT @cnt=COUNT(*) FROM customers WHERE City = @city' EXECUTE sp_executesql @sqlCommand, N'@city nvarchar(75),@cnt int OUTPUT', @city = @city, @cnt=@counts OUTPUT select @counts as Counts

Monday, March 9, 2015

I had a situation where I had to loop through a list of database connections and if one of the database connection was down the flow had to continue to the next database.

This is how I achieved it -

1. The list of database connections ( the result returned by the Execute SQL task : Retrieve hospital list ) was assigned to the user variable @HospitalList ( type Object)  and the list was assigned as  the enumerator  for the Foreach loop  show in the following diagram.






The Script editor had the following code.

public void Main()


{
// TODO: Add your code here

bool failure = false;

bool fireAgain = true;

foreach (var ConnMgr in Dts.Connections)


{
Dts.Events.FireInformation(1, "", String.Format("ConnectionManager='{0}', ConnectionString='{1}'",

ConnMgr.Name, ConnMgr.ConnectionString), "", 0, ref fireAgain);

try


{
ConnMgr.AcquireConnection(null);

Dts.Events.FireInformation(1, "", String.Format("Connection acquired successfully on '{0}'",

ConnMgr.Name), "", 0, ref fireAgain);


}
catch (Exception ex)


{
Dts.Events.FireError(-1, "", String.Format("Failed to acquire connection to '{0}'. Error Message='{1}'",


ConnMgr.Name, ex.Message),
"", 0);

failure = true;


}

}
if (failure)

Dts.TaskResult = (int)ScriptResults.Failure;

else

Dts.TaskResult = (int)ScriptResults.Success;


}

}

}


The Precedence Constraint Editor for the success flow was set as follows



 
 
 
The Precedence Constraint Editor for the failure was set as follows.
 
 
Note: The connection string of the database was dynamically created . The connection string was stored in a database table which was read by the Execute SQL task : Retrieve hospital list