Getting Request Timeout sometimes from only one SP? - sql

Question

I have a lot of stored procedures. But I am only getting Request Timeout sometimes only for this SP ?
ALTER PROCEDURE [dbo].[Insertorupdatedevicecatalog]
(#OS NVARCHAR(50)
,#UniqueID VARCHAR(500)
,#Longitude FLOAT
,#Latitude FLOAT
,#Culture VARCHAR(10)
,#Other NVARCHAR(200)
,#IPAddress VARCHAR(50)
,#NativeDeviceID VARCHAR(50))
AS
BEGIN
SET NOCOUNT ON;
DECLARE #TranCount INT;
SET #TranCount = ##TRANCOUNT;
DECLARE #OldUniqueID VARCHAR(500) = ''-1'';
SELECT #OldUniqueID = [UniqueID] FROM DeviceCatalog WHERE (#NativeDeviceID != '''' AND [NativeDeviceID] = #NativeDeviceID);
BEGIN TRY
IF #TranCount = 0
BEGIN TRANSACTION
ELSE
SAVE TRANSACTION Insertorupdatedevicecatalog;
DECLARE #Geo GEOGRAPHY = geography::STGeomFromText(''POINT('' + CONVERT(VARCHAR(100), #Longitude) + '' '' + CONVERT(VARCHAR(100), #Latitude) + '')'', 4326);
IF EXISTS(SELECT 1 FROM DeviceCatalog WHERE [UniqueID] = #UniqueID)
BEGIN
DECLARE #OldGeo GEOGRAPHY
,#OldCity NVARCHAR(100)
,#OldCountry NVARCHAR(100)
,#OldAddress NVARCHAR(100);
SELECT #OldGeo = [LastUpdatedLocationFromJob]
,#OldCity = [City]
,#OldCountry = [Country]
,#OldAddress = [Address]
FROM DeviceCatalog
WHERE [UniqueID] = #UniqueID;
UPDATE DeviceCatalog
SET [OS] = #OS
,[Location] = #Geo
,[Culture] = #Culture
,[Other] = #Other
,[IPAddress] = #IPAddress
WHERE [UniqueID] = #UniqueID;
IF (#OldGeo IS NULL OR #OldAddress IS NULL OR #OldCity IS NULL OR #OldCountry IS NULL OR ISNULL(#Geo.STDistance(#OldGeo) / 1000,0) > 50)
BEGIN
UPDATE DeviceCatalog
SET [Lastmodifieddate] = Getdate()
WHERE [UniqueID] = #UniqueID;
END
END
ELSE
BEGIN
INSERT INTO DeviceCatalog
([OS]
,[UniqueID]
,[Location]
,[Culture]
,[Other]
,[IPAddress]
,[NativeDeviceID])
VALUES (#OS
,#UniqueID
,#Geo
,#Culture
,#Other
,#IPAddress
,#NativeDeviceID);
IF(#OldUniqueID != ''-1'' AND #OldUniqueID != #UniqueID)
BEGIN
EXEC DeleteOldAndroidDeviceID #OldUniqueID, #UniqueID;
END
END
LBEXIT:
IF #TranCount = 0
COMMIT;
END TRY
BEGIN CATCH
DECLARE #Error INT, #Message VARCHAR(4000), #XState INT;
SELECT #Error = ERROR_NUMBER() ,#Message = ERROR_MESSAGE() ,#XState = XACT_STATE();
IF #XState = -1
ROLLBACK;
IF #XState = 1 AND #TranCount = 0
rollback
IF #XState = 1 AND #TranCount > 0
ROLLBACK TRANSACTION Insertorupdatedevicecatalog;
RAISERROR (''Insertorupdatedevicecatalog: %d: %s'', 16, 1, #error, #message) ;
END CATCH
END

Answer 1

The timeout occurs due to two updates to same table inside same transaction. You could avoid it with a case statement. Also whole IF ELSE can be replaced with a merge.
MERGE INTO DeviceCatalog DC
USING (SELECT #UniqueID AS UniqueID) T ON (DC.UniqueID = T.UniqueID)
WHEN MATCHED THEN
UPDATE SET [OS] = #OS
,[Location] = #Geo
,[Culture] = #Culture
,[Other] = #Other
,[IPAddress] = #IPAddress
,[Lastmodifieddate] = (CASE
WHEN (LastUpdatedLocationFromJob IS NULL OR [Address] IS NULL OR [City] IS NULL OR [Country] IS NULL OR ISNULL(#Geo.STDistance(LastUpdatedLocationFromJob) / 1000,0) > 50)
THEN Getdate()
ELSE [Lastmodifieddate]
END)
WHEN NOT MATCHED THEN
INSERT INTO DeviceCatalog
([OS]
,[UniqueID]
,[Location]
,[Culture]
,[Other]
,[IPAddress]
,[NativeDeviceID])
VALUES (#OS
,#UniqueID
,#Geo
,#Culture
,#Other
,#IPAddress
,#NativeDeviceID)
WHEN NOT MATCHED BY SOURCE AND #OldUniqueID != ''-1'' AND #OldUniqueID != #UniqueID THEN
DELETE;
Try it and check whether this is what you expected.

Answer 2

Already discussed here
You can achieve it using sp_getapplock in TSQL.
But you need a wrapper storedproc or batch for this. Check the following example it will help you to desing your wrapper sp/batch statement.
Sample Code Snippet
Create table MyTable
(
RowId int identity(1,1),
HitStartedAt datetime,
HitTimestamp datetime,
UserName varchar(100)
)
Go
Create proc LegacyProc (#user varchar(100), #CalledTime datetime)
as
Begin
Insert Into MyTable
Values(#CalledTime, getdate(), #user);
--To wait for 10 sec : not required for your procedures, producing the latency to check the concurrent users action
WAITFOR DELAY '000:00:10'
End
Go
Create Proc MyProc
(
#user varchar(100)
)
as
Begin
Declare #PorcName as NVarchar(1000), #CalledTime datetime
Begin Tran
--To get the Current SP Name, it should be unique for each SP / each batch
SET #PorcName = object_name(##ProcID)
SET #CalledTime = Getdate()
--Lock the Current Proc
Exec sp_getapplock #Resource = #PorcName, #LockMode = 'Exclusive'
--Execute Your Legacy Procedures
Exec LegacyProc #user, #CalledTime
--Release the lock
Exec sp_releaseapplock #Resource = #PorcName
Commit Tran
End

Answer 3

You are doing two seperate updates on the DeviceCatalog table where [UniqueID] = #UniqueID in the same transaction.
I bet your locking/request timeout issue is happening when:
IF (#OldGeo IS NULL OR #OldAddress IS NULL OR #OldCity IS NULL OR #OldCountry IS NULL OR ISNULL(#Geo.STDistance(#OldGeo) / 1000,0) > 50) is true.
Try something like this in place of the two updates.
Obviously test in dev first.
In the else clause, you want to have it insert something if the when is false. Here I am just inserting the current before update field contents.
UPDATE DeviceCatalog
SET [OS] = #OS
,[Location] = #Geo
,[Culture] = #Culture
,[Other] = #Other
,[IPAddress] = #IPAddress
,[Lastmodifieddate] =
case when (
#OldGeo is NULL
OR
#OldAddress is NULL
OR
#OldCity is NULL
OR
#OldCountry is NULL
OR
ISNULL(#Geo.STDistance(#OldGeo) / 1000,0) > 50
) then Getdate()
else [Lastmodifieddate]
end
WHERE [UniqueID] = #UniqueID