New Features in dotConnect for Oracle 9.11

February 20th, 2020

Devart is glad to announce the new version of our ADO.NET provider for Oracle with advanced ORM support – dotConnect for Oracle 9.11. The new release contains a huge set of new features, Direct mode improvements, and Oracle-specific technologies support: support for Oracle Sharding, Query Result Change Notification, OracleCredential class to specify password as a SecureString, SSL/TLS support in the Direct mode, .NET Standard/.NET Core support improvements, and many more.

Oracle Sharding Support

Oracle Sharding technology allows splitting a database into multiple ones – database shards, hosted on different physically independent servers, and work with it transparently as with single logical database – sharded database. This technology is based on partitioning a hierarchy of tables, linked by master-detail relationships, horizontally, when rows go to different partitions based on values in the topmost parent table columns, which are referenced by all the tables in the hierarchy. These columns are called sharding key. And these different partitions are stored in different shards.

Applications are not required to know anything about database sharding, and can connect to a sharded database completely transparently, like with any non-sharded Oracle database. However, in such case queries may often need to run against all the shards, and in certain cases it may lead to inefficient resource use.

Sharded databases provide many performance benefits – linear scalability, geographical data distribution, etc. But the best practice is when an application mostly uses small short-living sessions that work only with a limited set of data from a single shard – perform single-shard queries. In this case, such a connection can specify the necessary value of the sharding key, and this allows connecting to a specific shard, where the needed data is stored, without the need to query other shards. This ensures the best performance and most efficient resource use.

dotConnect for Oracle now provides the OracleShardingKey class and SetShardingKey method of OracleConnection that allow you to specify sharding key and perform single shard queries most efficiently. Oracle Sharding is supported only in the OCI mode. You can find more details about Oracle Sharding support in our documentation.

OracleCredential Class

The new OracleCredential class allows specifying credentials for connecting to Oracle in a more secure way than a plain-text connection string. It stores password as a SecureString, which is encrypted in unmanaged memory on Windows platform. Note that it is supported only in the OCI mode.

Query Result Change Notification Support

Query Result Change Notification (QRCN) is a part of Oracle’s Continuous Query Notification technology, and it allows client application to register a query for notifications when its result data changes in the database. Unlike the Object Change Notification, previously supported in dotConnect for Oracle, notifications are sent in case of changes in the query result set, not any changes in queried objects.

We have updated the OracleDependency class and other classes implemented previously for Object Change Notification support, and now you can use them for both parts of Oracle’s Continuous Query Notification technology. See our documentation for more information.

SSL/TLS Support in Direct Mode

With the new version of dotConnect for Oracle, you can use SSL/TLS encryption in the Direct mode as well as in the OCI mode. You can either use certificates from Oracle Wallet, stored in the registry or in a file, or from Microsoft Certificate Storage, or simply encode it to a base64 string and specify it as a connection string parameter.

To enable SSL in OracleConnection, you may either add “tcps://” to the beginning of the Server connection string parameter or specify it as a full TNS descriptor, including PROTOCOL set to tcps.

.NET Standard Support Improvements

New version of dotConnect for Oracle contains a new set of assemblies, compatible with .NET Standard 2.1, which allow selecting OracleHome to use, unlike assemblies for lower .NET Standard versions. Additionally, OracleDataTable and OracleDataSet classes are now available in .NET Standard compatible assemblies.

Other Improvements

This is not a complete list of dotConnect for Oracle improvements. Other new features include support for connecting using SYSRAC role, GetSchema method improvements, SSIS 2019 support, etc. You can see the list of changes on the product history page.

You are welcome to download the updated version of dotConnect for Oracle and send feedback.

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