Mashed Articles

My latest post is about how maintaining MSDB database, today I would like to share with you some thoughts about maintaining Sharepoint databases.

Last week I visited our client who has been working with SharePoint (MOSS7) and started complain about performance of SQL Server. I identified long running queries as well as very good number of deadlocks that happened every hour to databases which belong to SharePoint product. However , when I recommend to add some indexes on the tables people start almost crying not to do that as they were told that SharePoint databases are self managed product and DBA should not be touched it at all. It looks to me very strange , but that was my first experience with MOSS and I decided to do some searching on internet.

I found a couple of documents (even published by MS) to read them as if Sharepoint SQL Server performance can be managed by Shrinking & Defragging the DB.
I also asked some Sharepoint people and they say that accessing the database directly, changing anything on their databases
aside from what’s provided out of the box, etc. is not supported unless you
do it thru the Sharepoint API. Hmm…. looks strange , does not?

Finally I ended up with sample script to identify very fragmented indexes and running ALTER INDEX index_name ON tablename REORGANIZE;

PS.
I could not imagine a customer being unwilling to create whatever indexes are
necessary to ensure reasonable performance of a production Sharepoint
system.

Hi folks. I’d like to share with you some technique to get a next value from the table means to create your own sequence mechanism.
As we all know that an Identity property may have gaps, so use the below script to retrieve a next value. We create a table with a one row and a only one column which holding the last used sequence value.

CREATE TABLE seq(col int not null);
INSERT INTO seq values(0);
go
SELECT * FROM seq

CREATE PROC spget_nextseq @next_val AS INT OUTPUT
AS
UPDATE seq SET @next_val= col = col + 1;
go

– usage
DECLARE @i as int;
EXEC spget_nextseq @i output;
SELECT @i;

Note, in OLTP application where many connections run this script you may end up with deadlocks. One way to pevent it is using lock hint called TABLOCK

ALTER PROC spget_nextseq @next_val AS INT OUTPUT
AS
UPDATE seq SET @next_val= col = col + 1 FROM seq WITH (TABLOCK);
go