SQL Server 2005 features

The SNC database interface supports several features that were introduced in SQL Server 2005. For more information about using these features, see the Microsoft SQL Server 2005 documentation.

Multiple Active Result Sets

The SNC interface supports Multiple Active Result Sets (MARS), which enable applications to have multiple default result sets open and to interleave reading from them. Applications can also execute statements such as INSERT, UPDATE, and DELETE and stored procedure calls while default result sets are open.

Encryption without validation

SQL Server 2005 always encrypts network packets associated with logging. If no certificate is provided on the server when it starts up, SQL Server generates a self-signed certificate that is used to encrypt login packets.

The SQL Native Client supports encrypting data sent to the server without validating the certificate. The TrustServerCertificate database parameter, available on the System page of the database connection profile dialog box, allows you to control this feature.

Snapshot isolation

The snapshot isolation level is designed to enhance concurrency for online transaction processing applications. Transactions that start under snapshot isolation read a database snapshot taken at start up time. Keyset, dynamic, and static server cursors in this context behave like static cursors opened within serializable transactions, but locks are not taken, which can reduce blocking on the server. The SQLCA.Lock value for snapshot isolation is SS. You can set this value in the Isolation Level field on the Transaction page of the database connection profile dialog box.