TITLE: Microsoft SQL Server Management Studio
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Failed to retrieve data for this request. (Microsoft.SqlServer.Management.Sdk.Sfc)
For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&LinkId=20476

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ADDITIONAL INFORMATION:

An exception occurred while executing a Transact-SQL statement or batch. (Microsoft.SqlServer.ConnectionInfo)
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The server principal "my_db_user" is not able to access the database "any_other_db_on_the_server" under the current security context. (Microsoft SQL Server, Error: 916)

For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&ProdVer=09.00.1399&EvtSrc=MSSQLServer&EvtID=916&LinkId=20476

This is something similar to the image below:

Error Connecting to MS SQL 2005 DB Remotely Management Studio 2008

This error happen to appear while remotely connecting a database on Microsoft SQL server 2005 with any version of Microsoft SQL Server Management Studio 2008, It will not appear if you connect the SQL server 2005 with Microsoft SQL Server Management Studio Express 2005. And the link that has been specified in the error above is of any no use, also the error started to be reported more for a Windows Shared hosting clients rather than the one with Windows dedicated server. Because the problem only appears to happen if you connect with a user that has access to a particular database and not with the user that has administrator access over the Microsoft SQL server. I had to scratch my head for the solution as it seems to be related more to the permissions on the database user. Now the interesting thing here is that the SQL database that in the error is different than the MSSQL database on which the user has its access on.

After allot of searching on the web I found that this is a bug on all versions of Microsoft SQL Server Management Studio (Express) 2008 and there is a simple work around to access your database remotely with no errors at all. Here is what that is required:

1) Connect to the MS SQL server with the user credentials in MSSMS (Express) 2008.
2) Bring Object Explorer Details window by selecting View –> Object Explorer Details in menu (or just by hitting F7)
3) In Object Explorer window click at Databases folder
4) In Object Explorer Details Window right-click at the column header and deselect Collation
5) Refresh Databases folder.

Refer to the image below for better understanding:

Fix Failed to retrieve data for this request Error: 916 Management studio

That is it. This will give you the desired access over your database and you will be happily make changes as per your need.
This is just another complicated error by Microsoft which has a very simple fix.

Local Group Policy:
Using local Group Policy involves setting up Group Policy on the local machine.This is not very useful for managing computers on a network. Local Group Policy is configured on the local computer.

Site Group Policy:

Site Group Policy is when the Group Policy object is linked to the site. Site Group Policies can generate unwanted network traffic, so use these only when absolutely necessary.

Domain Group Policy:
Domain Group Policy is when the Group Policy object is linked to the domain.This will apply the Group Policy object to all computers and users within a domain.This is especially useful for enforcing company-wide settings.This is one of the two most commonly used applications of Group Policy.

Organizational Unit:
Group Policy When the Group Policy object is linked to the organizational unit (OU). Organizational unit Group Policy is especially useful for applying a Group Policy object to a logical grouping (organizational unit) of users or computers.

When a Windows Server machine logs on to a Windows AD, any legacy Windows 2000 Group Policies will be applied to and work on Windows Server. The new Windows Group Policy snap-in will work on a Windows 2000 AD as well as Windows 2003.You can use the Windows Group Policy snap-in to connect to any Group Policy object in the Active Directory.You can also create a new Group Policy object using this snap-in. When you connect to a GPO using this snap-in, the ADM files are automatically updated using the newer versions of these files found on Windows XP.

Windows has over 200 policies.These policies are reflected in the new ADM files that are updated on the domain.The Windows admin snap-in shows what policies work on which clients. Best practice in a mixed environment: Use the Latest Windows Group Policy snap-in to administer Group Policy because it will display what policies are supported on what clients.

Group Policy Order

When Group Policies are applied in Windows Server, they are applied in a specific order.This is important to note because the order applied can affect the resulting policy. Group Policy is applied in the following order:

■ Windows NT 4 Policies (if any exist)
■ Windows 2000 Policies
■ Local Group Policies
■ Site Group Policies
■ Domain Group Policies
■ Organizational Group Policy Objects (going from Highest Parent in the chain to lowest)

Additionally, the result of all of the applied policies can be determined by using the Resultant Set of Policy (RSOP) snap-in. More information on this topic is covered later in the “Resultant Set of Policy (RSOP)” section. Figure A.1 shows how Group Policy is applied by different organizational units along with the domain Group Policy.

After installing a SQL Server failover cluster, the node hosting the SQL Server resource uses the Service Control Manager to check every 5 seconds whether the SQL Server service appears to be running. This “LooksAlive” check does not impact the performance of the system, but also does not do a thorough check; the check will succeed if the service appears to be running even though it might not be operational. Because the LooksAlive check does not do a thorough check, a deeper check must be done periodically; this “IsAlive” check runs every 60 seconds.

The IsAlive check runs a SELECT @@SERVERNAME Transact-SQL query against SQL Server to determine whether the server can respond to requests. Although a reply to the IsAlive query confirms that the SQL Server service is available for requests, it does not guarantee that all user databases are available, or that the user databases are operating within necessary performance/response-time requirements.

If the IsAlive query fails, the IsAlive health check is retried five times and then it attempts to reconnect to the instance of SQL Server. If all five retries fail, the SQL Server resource fails. Depending on the failover threshold configuration of the SQL Server resource, the failover cluster will attempt to either restart the resource on the same node or it will fail over to another available node. The IsAlive query tolerates a few errors, but ultimately it fails if its threshold is exceeded.

During failover of the SQL Server instance, SQL Server resources start up on the new node. Windows clustering starts the SQL Server service for that instance on the new node and SQL Server goes through the recovery process to start the databases. After the service is started and the master database is online, the SQL Server resource is considered to be up. Now the user databases will go through the normal recovery process, which means that any completed transactions in the transaction log are rolled forward (the Redo phase), and any incomplete transactions are rolled back (the Undo phase). In SQL Server 2005 Enterprise Edition, each user database will be available to the user once the Redo phase completes; for the other editions, as with all previous versions, each user database is unavailable until the Undo phase completes. The length of the recovery process depends on how much activity must be rolled forward or rolled back upon startup. The ‘recovery interval’ sp_configure option of the server can be set to a low number to avoid longer Redo recovery times and to speed up the failover process. The Undo recovery time can be reduced by using shorter transactions so that any uncommitted transactions do not have much to roll back.

EFS can be used to encrypt SQL Server 2005 data files and folders. EFS is supported on Windows 2000 and later operating systems with New Technology File Systems (NTFS) formatted drives. EFS uses a combination of symmetric and asymmetric methods to provide transparent SQL Server 2005 data encryption. On Windows 2003 Server and newer operating systems, EFS by default creates a random File Encryption Key, which is a 256-bit AES key to perform data encryption.The File Encryption Key is then itself encrypted with the user’s public key and stored within the encrypted file or folder.

To encrypt SQL Server 2005 data files and folders using EFS, follow these steps:

1. Stop the SQL Server service.
2. Log out and log in using the SQL Server service account credentials.
3. Right-click on the file or folder to be encrypted and select Properties | General Tab | Advanced.

4. Within the Advanced attributes window, select Encrypt contents to secure data.
5. Within the Advanced attributes window, press OK.
6. Within the Properties tab, press OK.
7. If you are encrypting a folder containing subfolders, you will be presented with another window asking if you would like to  encrypt them as well. Press OK.
8. EFS encrypted files and folder names should now appear in green within any Windows file explorer window.
9. Restart the SQL Server services.

If errors are generated, you may have encrypted the SQL Server data files using an account that is not linked to the SQL Server service account.You can decrypt the data folders by reversing the steps above and trying again. When encrypting individual database files, EFS first creates a plain text copy of the file to be encrypted, encrypts the target file, and then deletes the temporary file.This temporary file is not securely deleted and can be recovered using common data recovery tools. To prevent local file disclosure, you should use a secure data deletion tool to overwrite the areas of disk containing the temporary file. Alternatively, you can simply encrypt the parent folder that contains the database files to ensure any temporary files are also encrypted.

EFS encryption is beneficial if the database media is stolen or misplaced. When transferring EFS encrypted files over the network, Windows first decrypts the file and then transfers the plain text equivalent. Some administrators perform manual backups of database files prior to implementing changes on the database server. If this backup involves copying data files from one server to another, you will effectively be storing an unencrypted copy of your database on the destination server.

Encryption File System Contains Inherit Flaws

On Windows Server 2003, EFS uses a strong 256-bit AES key to encrypt data. Under most circumstances, this would be an effective method of encryption; however, this AES key is protected by the user’s public key, which is based on the user’s Windows login password. This ultimately reduces EFS protection to the strength of the user’s Windows password. There are publicly available tools that can successfully decrypt EFS encrypted data by exploiting this flaw. Because of this, EFS should not be used to encrypt sensitive database data.

Working with EFS Encrypted Data

EFS encryption is managed by the operating system, and seamlessly provides file and folder encryption to SQL Server 2005. All SQL Server functions and operations remain unchanged when using this encryption method. Because EFS is handled outside of SQL Server 2005, encryption keys must be backed up separately in addition to your database backups.

MS SQL 2005 Server was released after 5 servers of it previous SQL version, MS SQL 2000, Hence it required allot to revisions to cope up with the current windows development environment. Therefore MS SQL 2005 SP2 had major changes in it, with too many performances and security fixes. Microsoft could not add few revisions due to its basic development structure however they had all the scope to introduce them in SQL 2008 release. And indeed, MS SQL 2008 has many installation as well as performance fixes being applied to it and allowing Windows Administrators to have full control on SQL activities. The biggest advantage of SQL 2008 over SQL 2005 is the ability to manage and maintain server performance. SQL 2008 does not require too much resource which is the best deal for today’s Shared Hosting environment. Also an upper hand to whose to do not want to invest too much on hardware of their dedicated servers just to run SQL server on it.

I have tried to gather the major improvement introduced by Microsoft on SQL 2008 from Internet which is an advantage over SQL 2005 however it all depends on what features are useful to you in the development of your ASP .NET applications. But switching to Microsoft SQL 2008 is definitely going to improve the performance even if you don’t use any of the below feature. And not to forget that with the release of SQL 2008, Microsoft will announce “End Of Life” for SQL 2000 version, which will mean that there won’t be any official support or update release for SQL 2000.

Major difference between SQL 2005 and SQL 2008.

* Easy Upgrades: Version upgrades are now very easy and effective with SQL 2008.
* Resource Restriction Governor: We set a restriction on a users or groups from consuming high resources. This is a very good feature that can be used on Windows shared server with SQL database to maintain the performance.
* Dates and Times settings: New data types such as: Date, Time, Date Time Offset has been introduced.
* Improved Full Text Search: Ability to backup Native Indexes and also thesaurus them as metadata.
* External Key Management: This unique can store Keys separately and not with the data.
* Improved SQL Server Analysis Service: It now has improved Stacks and computes block faster.
* Improved Installation: Microsoft has added an option where you can uninstall Disk images and service packs.
* Data Synchronizing: A Development of databases used in applications that frequently get disconnected.
* Transparent Data Encrypts: It has the ability to encrypt full SQL database with different encryption Methods.

* SQL Server Integration Service: SQL 2008 Server has improved multiprocessor support and faster lookups in compare to SQL 2005.
* Change Data Capture: Allows all changes to be captured and queried. (Enterprise). Also allows us to get detailed information on what changes has happened to which rows after a specific version.
* LINQ: A Development query language for accessing multiple type of data like XML and SQL at the same time.
* Hot Plug CPU: With this feature to an add CPUs on fly for your SQL server to use.
* Microsoft Office 2007 integration: One can use MS OFFICE as an SSRS template, like SSRS to WORD.
* Spatial Data types: Data types for storing Longitude, Latitude and GPS entry of a particular database.
* MERGE: A new TSQL command as a combination Update, Insert and Delete.
* Encrypted Backups: We can execute it at the time running backups to prevent tampering from external resource.
* Data Compression: This feature is different as it allows us to manage data compression at table level to enhance performance.
* Dynamic Development: Latest Visual Studio and ADO options along with ASP .Net 3.
* Reporting Server Performance: Unlike in SQL 2005 we can set threshold on Reporting server for memory management.
* Performance Studio: It is a Gallery that has collection of monitoring tools enhanced performance.
* Audits: A very power feature for monitoring the data access of your SQL database.
* Table Value Parameters: SQL 2008 database has ability to insert entire table into a stored procedure.
* Entity Database Services: (LOB) Line Of Business framework and (eSQL) Entity Query Language.

No doubt that Microsoft has improved all the features that has been used by hosting services. Even SQL Cluster in version 2008 has few major advantages since every one in today world wants to have their site up all the time with 100% uptime. I hope I get some time to write on “MS SQL 2008 Clustering..“

A password that allows for spaces can be referred to as a pass phrase. The benefit of pass phrases is that you can make them meaningful and easy to remember. Instead of creating and managing encryption keys or certificates in your database server, you can encrypt data using only a pass phrase.The ENCRYPTBYPASSPHRASE statement uses the supplied pass phrase to generate a symmetric key, which is used to perform the actual data encryption. No key management is required, as the key will be recreated each time the same pass phrase is supplied.The common syntax of the ENCRYPTBYPASSPHRASE statement is as follows:

ENCRYPTBYPASSPHRASE ('PASSPHRASE', 'PLAINTEXT')

In this statement, PASSPHRASE specifies the data string to be used to derive an encryption key. PLAINTEXT specifies the data to be encrypted. No permissions are required to run the ENCRYPTBYPASSPHRASE statement.

The following syntax encrypts the string using the supplied pass phrase:

SELECT ENCRYPTBYPASSPHRASE('SQL Server 2005 Pass Phrase Encryption', 'pass phrase encryption test')

Here are the results:

0x01000000B0FA66E0152FB0B655B23439904E36F3ED5B758618BEED0F2A2BF918C6CF9DF685BC2A60A
AD5E81D660BA5A396D1CA89

As mentioned earlier, the preceding results will differ from what you receive on your SQL Server.To decrypt data, you can use the DECRYPTBYPASSPHRASE statement.The general syntax of this statement is as follows:

DECRYPTBYPASSPHRASE ('PASSPHRASE', 'CIPHERTEXT')

In this statement, PASSPHRASE specifies the data string to be used to derive a decryption key. CIPHERTEXT specifies the data to be decrypted. Similar to the ENCRYPTBYPASSPHRASE statement, no permissions are required to execute the DECRYPTBYPASSPHRASE statement.The following syntax uses the DECRYPTBYPASSPHRASE statement to decrypt the previously encrypted data, and converts it into the human readable varchar format:

SELECT CAST (DECRYPTBYPASSPHRASE('SQL Server 2005 Pass Phrase Encryption',
0x01000000B0FA66E0152FB0B655B23439904E36F3ED5B758618BEED0F2A2BF918C6CF9DF685BC2A60A
AD5E81D660BA5A396D1CA89) AS varchar)

Note that you should substitute the cipher text in the preceding statement with the cipher text that you obtained from the earlier ENCRYPTBYPASSPHRASE statement. Here is what the results of running the preceding statement will look like:

pass phrase encryption test

The encryption algorithm and key length used by pass phrase encryption have not been formally documented by Microsoft. Because of this, it is recommended that you do not use this encryption mechanism to encrypt sensitive data.

Flaws within Microsoft Object Encryption

The object encryption used by Microsoft is weak, and there are publicly available scripts that can successfully decrypt the objects. Further, at run-time, SQL Server internally decrypts the object and SQL Profiler can be used to capture object logic in plain text form. Due to this, object encryption should not be used to encrypt sensitive information, and you should not embed key or certificate passwords or pass phrases in SQL Server objects encrypted using objectbased encryption.