Kalen Delaney's seminar

Just backed home from the three days of seminar in Tel-Aviv named "Deep dive into SQL Server Internals with Kalen Delaney".
Two days Kalen explained about SQL Server Query Plans,Tuning and Recompile techniques and the last one was about SQL Server Data Storage Formats.

You know , I thought I know a lot about SQL Server performnace tunning and etc, however, attending that seminar I just realized how much I need to learn. There are lot if tips,thoughts how to tune the system, indexes and etc.

I would also mention about how easy was to understand Kalen (she spoke english at seminar :-)) and her methods to provide courses which is so important for attendants.

Don't speak to the DBA while he/she is doing the job.

Our DBA was very busy today, helped out our developers top write efficient code,explained to the programmer how to launch the old DTS package on SQL Server 2005 and etc. You know how it is, someone comes in and asking the question and you answer the question at the same time you are doing the work.
So,today answering one such questions our DBA deleted by mistake very ctitical database. Fortunately , we had zero data loss thanks to our backup/recovery strategy.

I think that is acceptable to say that you are busy right now please ask the question later on, what do you think?

Getting column level permision report

If you think about giving column level permission , you'll probably create a view with only needed columns to expose to ,then grant SELECT permission on that view and absolutely DENY access to underlaying tables to the user, right? Also , it depends on the policy of the company but you are able to grant SELECT/UPDATE/DELETE/INSERT operations on column level, have you ever used it:-)? So I recently visited our client who does perfom security permission on column level and wanted to know what are the columns and on what tables that specific user has access? I decided to perform the below testing, see if that might help you.

CREATE TABLE demo (c INT, c2 INT)

/* Grant SELECT permission on column named c on demo table*/
GRANT SELECT (c) ON demo TO test


EXECUTE AS USER = 'test';

SELECT * FROM fn_my_permissions('dbo.demo', 'OBJECT')
ORDER BY subentity_name, permission_name ;

REVERT

Have you dealt with ENTER key in INSERT table?

I have a client who uses the application that allows to insert data but also typing ENTER key in the middle. Well, the question is how do you want to store the data and later displaying on the client? He was not sure , so I showed him the below technique to display such kind of data....


--Create auxiliary table
SELECT TOP 8000 n = IDENTITY(INT)
INTO Numbers
FROM syscolumns s1, syscolumns s2 ;

CREATE TABLE test (col1 varchar(8000))

INSERT INTO test values ( 'Row----------1
Row--------2
Row--3
Row----4'
)

---See how it stores the data.
SELECT * FROM TEST

--Remove ENTER key
SELECT SUBSTRING(col1, n, CHARINDEX(CHAR(13), col1 + CHAR(13), n) - n)
FROM Numbers, test
WHERE SUBSTRING(CHAR(13) + col1, n, 1) = CHAR(13)
AND n < LEN(col1) + 1 ;

--Cleanup
DROP TABLE Numbers
DROP TABLE test

I was invited to blog on www.sqlblog.com

A few days ago Adam Machanic who is the owner of that great web site invited me to join his great company. I am really excited about and proud to be part of such great company of friends who write very good stuff about SQL Server.
I would like to keep bloging here as well , I do not know how long it will take but you can always catch me up on http://sqlblog.com/blogs/uri_dimant/

Think before unchecking sysadmin rights of BUILTIN\Administrators.

I have recently met our client who uchecked the sysadmin rights of BUILTIN\Administrators group before given any permissions to anotgher account.

That was NOT such problem if the BUILTIN\Administrators group was removed from sysadmin role accidentally/by mistake, then you must login with another sysadmin login. If there is no other sysadmin login, you must login with SQL authentication as sa with the password that was set during setup to sa. Once logged in as a member of sysadmin, you are able to add BUILTIN\Admisnitrators back to sysadmin role.
However everything above does not work for the client. Uhhh,the client also disabled SA accoount as well as DAC connection.
Moreover, there is no domain controller where you can create a sysadmin domain acoount and grant the access to the machine running SQL Server,that was a stand alone computer with single instance installed on.

The solution we found was to start SQL Server with single user mode. Using the single-user mode, SQL Server 2005 prevents a Windows Administrator to abuse this privilege to act on behalf of the sysadmin without being noticed. This allows Windows Administrator accounts to perform certain maintenance tasks, such as installing patches. To someone who is not familiar how to start the instance in single user mode and adding login to the server role being system administrator please read the below link describing step by step the procedure.

http://blogs.msdn.com/raulga/archive/2007/07/12/disaster-recovery-what-to-do-when-the-sa-account-password-is-lost-in-sql-server-2005.aspx

SQL_VARIANT_PROPERTY() to find the info about data type?

BOL says that this function returns the base data type and other information about a sql_variant value. Have you ever looked what is datatype of GETDATE() or perhaps DB_ID() function or what is the data type of SYSTEM_USER??

DECLARE @var sql_variant
SET @var =GETDATE() --SYSTEM_USER
SELECT SQL_VARIANT_PROPERTY(@var , 'BaseType') as BaseType
, SQL_VARIANT_PROPERTY(@var , 'Precision') as Precision
, SQL_VARIANT_PROPERTY(@var , 'Scale') as Scale
, SQL_VARIANT_PROPERTY(@var , 'TotalBytes') as TotalBytes
, SQL_VARIANT_PROPERTY(@var , 'MaxLength') as MaxLength
, SQL_VARIANT_PROPERTY(@var , 'Collation') as Collation;

I found that very usefull as you can easily retun the basic info about even system objects and how SQL Server interpetes it.