SQL 11–Denali Creating Server Roles

One of the neat new features of the new SQL Server, is the ability to create server roles, this was not possible before, you could only create a role on the database, and grant database level permissions to it. Now you can create a Server Role, and grant permissions to it, this allows us to group permissions and make then more visible, as its really boring to check every login for its server level permissions, so here’s how to use it.

The permissions you need for this are:

• CREATE SERVER ROLE, which is present at sysadmin server role.
• Impersonate if you set ownership for this role.

For a full doc check this link.

Just one note: a Server role cannot contain permissions for database level securables (objects).

I’m going to demonstrate how to create a server role, and add a user to it.
But first I’m going to create a SQL User for demonstration purposes.

CREATE LOGIN TEST
WITH PASSWORD = N'TEST'
,CHECK_EXPIRATION = OFF
,CHECK_POLICY = OFF
GO

Then we get to the feature display:

CREATE SERVER ROLE VIEW_STATE
GO
GRANT VIEW SERVER STATE TO VIEW_STATE
GO
ALTER SERVER ROLE VIEW_STATE
	ADD MEMBER TEST
GO

Note that on the first statement we’re creating the role with the name of SERVER_STATE, then we’re adding the permission VIEW SERVER STATE to the role, and finally adding the user to the role, notice how we add the user to the role, its pretty different that the database role which uses the sp_addrolemember procedure.

Well I hope’s this helps you see some of the goodness that the new SQL 11 will bring us.

Greetings from the
Developer Seer

The New TSQL Code snippets from SQL 11–Denali

I posted the features that I liked most before on my post about where to download the new CTP1 of SQL Denali.

One of them were TSQL Code snippets.

This post will have some screenshots about the new feature, and how to use it.

My opinion on this feature is that it is awesome, and it still needs improvement.

The MS books online of this feature is on this link.

So its Just Open up the new SQL Server Management Studio.

Open a New Query, and press 

Ctrl K + Ctrl X

You will see this window:

Now if you select Function and Create Multi-Statement Table Function

You’ll see this script being added to the window.

Note the highlighted areas, the current area I am editing is the schema, however if I edit for example the parameter name, it will be updated across the script.

It works a little like the Visual Studio .NET Snippets, however for developers the snippets are really more powerful, lets hope this feature gets improved, as the potential for this is Huge.

Well this was fun, hope this gets you excited about what's coming next on the next version of SQL.

Greetings for all,
The Developer Seer.

Error 0x80010105 on SQL 2008 R2 Configuration Manager

Today I faced this problem and wanted to share it, When going to SQL Configuration Manager and clicking on SQL Server Services I was simply presented a error that said
“The server threw an exception. [0x80010105]”
with a little red icon of error, and no refresh would save us.
So I googled it a bit and found this blog post.
http://aspdotnetdevelopment.wordpress.com it’s a blog about ASP.NET, MVC and SQL.
And the owner of the blog says it’s a WMI problem, so go on and restart it’s service.
The solution is on Start –> Run –> services.msc –> Find “Windows Management Instrumentation” –> and Click Restart.
He also points that the solution came from here:
http://social.msdn.microsoft.com/Forums/en/sqldatabaseengine/thread/f7fc2002-169c-42a4-8bdf-2dc4a751f950
So Thanks to WeiLin Qiao and to the above cited blog I’ve solved my problem, and hope it helps you solve yours if you happen to have this problem.
Good Luck and Farewell.
The Developer Seer.

SQL Server 11–Denali CTP 1 is available for download

Few know that the next version of SQL Server that is being developed as we speak already has a first release ready for tests!
Its called Community Technology Preview after all, so we the SQL Server community can test it and send feedback to Microsoft.
So where is it and what's new ?
Download it HERE.
What's New???
Here’s the official list.
Things that caught my attention:

• The new SEQUENCE (know in Oracle)
• A New SQL Way of doing Server Side Pagination
• Now you can create Server Level Roles
• TSQL Code Snippets on Management Studio
• And The new Project Crescent

About how to send feedback is unknown, the only place I know that we can send feedback to Microsoft is the Connect site.
The Developer Seer wish's you a good study.
Greetings,
The Developer Seer.

Find SQL Default Data and Log Directories using TSQL Independent of Instance name or Cluster Installation

 

Hello, I was needing this function for some reason and I though someone else may need it.

So basically this info we are wanting is the default place where SQL will place the Data and Log Files, this will be brought when you try to restore a database using the GUI, if you’re not using the GUI you’ll have to know the directories.

Well SQL just doesn’t have a Custom Function for finding these directories, its not contained on SQL itself, SSMS shows you if you right-click the server you’re connected and select properties, then selecting Database Settings, but other than that the only way to know this info is by looking it up on the windows registry.

So how do we need to look in the registry with TSQL, we also need to check the right place because if you are running a named instance this values will be on a different place that they would be if we were querying a default instance, the same for a clustered instance.

So How do we go through this?

Well there's a procedure called XP_INSTANCE_REGREAD, if we were just reading any key on the registry we would be using xp_regread, but we need this info regardless of instance, so this xp_instance_regread will do the job of localizing which instance we’re currently using.

Now we need to query two registry keys one for the data directory and another for the log, however on cluster installations the Data directory is located on another key, so just using xp_instance_regread won’t save us this time, we’ll have to manually check for this. So on the code I expose bellow I'm checking first on the registry key that is not the one for the cluster and if the value is not there I’ll read the cluster one, that way we’ll get the value always.

The Keys are (remember Instance aware):

For Data: HKLM\Software\Microsoft\MSSQLServer\MSSQLServer
and Value DefaultData

For Log: HKLM\Software\Microsoft\MSSQLServer\MSSQLServer

and Value DefaultLog.

So now here’s the code.

declare @datadir nvarchar(4000)
        ,@logdir nvarchar(4000);

EXEC master.dbo.xp_instance_regread 
    N'HKEY_LOCAL_MACHINE'
    , N'Software\Microsoft\MSSQLServer\MSSQLServer'
    , N'DefaultData'
    , @datadir output;

IF @datadir IS NULL
BEGIN
EXEC master.dbo.xp_instance_regread 
    N'HKEY_LOCAL_MACHINE'
    , N'Software\Microsoft\MSSQLServer\Setup'
    , N'SQLDataRoot'
    , @datadir output;
END
EXEC master.dbo.xp_instance_regread 
    N'HKEY_LOCAL_MACHINE'
    , N'Software\Microsoft\MSSQLServer\MSSQLServer'
    , N'DefaultLog'
    , @logdir output;

SELECT @datadir as Data, ISNULL(@logdir,@datadir) as Log;

Hope this helps you!

Kind Regards,
The Developer Seer.

CHECKDB WITH DATA_PURITY

I’ve Learned this recently, about two months ago.

Again on Paul Randal’s blog, click here if you want to see the post.

The thing is SQL 2005 introduced a check on DBCC CHECKDB, that checks for columns values like, is my column values within range of my selected data type?

When migrating databases I’ve seen some negative DateTimes (which Query Analyzer does display, some weird float values that even query analyzer does not display)

The First question you might have is how the hell did this values get in there?
Well… On SQL 2000 and bellow, SQL allowed data Import without some checking with ended up with those values in there.

If you created the database on SQL 2005, this check is always done when you issue a:

DBCC CHECKDB ([db_name])

if your database is from a SQL 2000, you may have to perform a explicit check, and once this check is completed successfully a value is changed in the database boot page, so SQL know that it passed once and will enforce checking every time.

Here’s the code for an explicit check:

DBCC CHECKDB ([db_name]) WITH DATA_PURITY

Remember to change the db_name for your database name, ok?

If you got any problem with the invalid values know you have two choices, and I don’t like any of them.

1. You can delete those rows. (lame solution right).
2. You can update the values for those rows, but probably you won’t be able to see what’s currently stored if you get this problem.

For more information around this you can check this MS KB. 

Database Maintenance–Part 1–Corruption

 

SQL Server is a Database System that needs maintenance and proper care!

Face it, realize it. The faster you realize this, the faster you can start researching why and how to take good care of your Database System.

Now, don’t illude yourself. Every RDBMS system will need care.

Never, ever Install a Database System and leave it there, things don’t work that way. As I said you have to maintain the system.

This is Part 1 and it only concentrate on detecting corruption.

I’ll update this with links for the next parts!

So I’ll skip the Why you need to do this, maybe when I can fully understand all SQL subsystems (SQL engine is huge).

So lets get into the How you maintain a database system.

Its important to understand that SQL Database files stand on a Hard Drive, and this files are under a whole I/O subsystem. You need to be aware of this because well, if a failure occur on the I/O subsystem database corruption may occur, and the worst part of it, you may not even know it, data that is not frequently read is never out of the disk, so its never checked for corruption, so this kind of corruption may only be noticed when you select some data that is corrupt. Fortunately there's a kind of protection that is a CHECKSUM per page that can be enabled on a database that will do a calculation for the bytes on the page and will prevent the corruption when writing the page to disk, and detect when reading from disk. This helps detects corruption, otherwise you wouldn’t even know if your data is corrupt.

So if you don’t have it enabled please do.

ALTER DATABASE [database_name] SET PAGE_VERIFY CHECKSUM;

This is a Best practice. But this only helps detect some corruptions, there are other and you should always have a Consistent database (I mean all databases).

The only way to recover from corruption without Backups and Replication is loosing the corrupt data. So One reason you need to maintain your databases are because well they can become corrupt and you need to investigate, is my data ok? Is there any corruption on my database? Is all the data on my database OK?

If you want to know really really really (have I said enough really?) deep about corruption you may want to check Paul’s Randal Blog – In Recovery. This man really know a lot, he used to work for Microsoft and was one of the responsible for writing one of SQL routines for checking corruption.

So if you understood well, how do you check your database?

there are tons of commands but the most used is DBCC CHECKDB.

This is a pretty heavy command, as it checks the whole DB, the bigger the database the longer it takes, at least this is How I think it is.

So How do I check my Database?

DBCC CHECKDB ([database_name])

Don’t worry this command will not change anything, it will only check.

Pray that it won’t find anything, I have found corruption before and it ain’t nice.

you have to make this check regularly, but do it on a window. If you can do it daily, but if you can’t do it weekly, if you database is really huge, there are other ways, check Paul Randal’s blog.

Well there are 3 things you can do to protect from corruption.

1 – Turn Checksum on a page level.

2 – Check your database regularly.

3 – Take Backups, Lots of them, but not just any Backup, you have to take the right ones. I’ll do post more info around Backups later. But why is taking backups necessary to protect from corruption, well the thing is you can’t escape from corruption without data loss unless you have a backup (or loads of them). And please if you take a backup check if it’s ok, there’s a really nice command which I’ll post about it that verifies the backup.

Well to sum up. Checking your database will not prevent future corruptions, it will only evaluate your database for corruptions Now. There’s “nothing” that can prevent you from future corruptions, only proper database maintenance can help you on that.

Now Do yourself a favor and schedule a job that does check all your databases on the night and mail you if there is an error on the job.

Hope this helps.
Good Luck
The Developer Seer.