Deadlock in SQL Server - sql-server

Question

I'm facing deadlock
was deadlocked on lock resources with another process and has been
chosen as the deadlock victim.
problem In SQL-Server as i'm inserting data in database by picking max id against a specific column then add a increment got the value against which record will be inserted.
i'm calling a procedure as code mentioned below:
CREATE
PROCEDURE [dbo].[Web_GetMaxColumnID]
#Col_Name nvarchar(50)
AS
BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
DECLARE #MaxID BIGINT;
SET NOCOUNT ON;
-- Insert statements for procedure here
BEGIN
BEGIN TRAN
SET #MaxID = (
SELECT Col_Counter
FROM Maintenance_Counter WITH (XLOCK, ROWLOCK)
WHERE COL_NAME = #Col_Name
)
UPDATE Maintenance_Counter
SET Col_Counter = #MaxID + 1
WHERE COL_NAME = #Col_Name
COMMIT
END
SELECT (
CONVERT(
VARCHAR,
(
SELECT office_id
FROM Maintenance
)
) + '' + CONVERT(VARCHAR, (#MaxID))
) AS MaxID
END
any one help me out .....

Answer 1

As Marc already answered, use SEQUENCE. It's available in all supported versions of SQL Server, ie 2012 and later. The only reason to avoid it is targeting an unsupported version like 2008.
In this case, you can set the counter variable in the same statement you update the counter value. This way, you don't need any transactions or locks, eg:
declare #counterValue bigint
UPDATE Maintenance_Counter
SET Col_Counter = Col_Counter + 1 , #counterValue=Col_Counter+1
WHERE COL_NAME = #Col_Name
select #counterValue

Answer 2

Yo can use sequences to generate incremental values avoiding any blocking.
I have adapted my own Counter Generator to be a direct replacement for yours. It creates dynamically the SQL statements to manage sequences, if a Sequence doesn't exist for the value we are looking for, it creates it.
ALTER PROCEDURE [dbo].[Web_GetMaxColumnID]
#Col_Name nvarchar(50)
AS
declare #Value bigint;
declare #SQL nvarchar(64);
BEGIN
if not exists(select * from sys.objects where object_id = object_id(N'dbo.MY_SEQUENCES_' + #Col_Name) and type = 'SO')
begin
set #SQL = N'create sequence dbo.MY_SEQUENCES_' + #Col_Name + ' as bigint start with 1';
exec (#SQL);
end
set #SQL = N'set #Value = next value for dbo.MY_SEQUENCES_' + #Col_Name;
exec sp_executesql #SQL, N'#Value bigint out', #Value = #Value out;
select #Value ;
END
The only inconvenience is that your values can get gaps within (because you could have retrieved a value but finally not used it). This is not a problem on my tables, but you have to consider it.