.NET Driver release notes for 2024¶

BCR (Behavior Change Release) changes¶

Beginning with version 4.0.0, the .NET driver introduced the following breaking changes:

• Connection pool behavior changes:

  • The driver now uses separate pools for each unique connection string. Previously, the driver use only one pool for all connection strings.

  • The maxPoolSize parameter change:

    • Previously, it represented the number of connections to store in the pool. Now it defines the maximum number of connections allowed to open for a given pool (for each unique connection string there is a different pool so you can set it differently for each of them).

    • If maxPoolSize is reached, the thread requesting a new connection waits until any connection from the pool is available to reuse without exceeding the limit. An exception is thrown in case of a timeout.

    • You can configure the waiting time in the connection string by setting the waitingForIdleSessionTimeout property. The default value for the timeout is 30 seconds. You can change it to 0 to disable waiting.

    • The default value for maxPoolSize is 10. Make sure your maxPoolSize value is properly set for your needs to avoid hanging your threads or timeout exceptions.

    • The maxPoolSize property should be greater than or equal to minPoolSize.

  • Added a new minPoolSize parameter with a default value of 2 that makes the driver open two connections (the second one in background) when you open the first connection for a given connection string. You can set this value to 0 in the connection string if you want to disable the minPoolSize feature.

  • The configuration of the pool has been changed to a connection string driven approach. All properties that control the connection pool behavior can be now passed in the connection string. It is no longer possible to set connection pool properties by SnowflakeDbConnectionPool setters, such as SnowflakeDbConnectionPool.SetTimeout, SetPooling, or SetMaxPoolSize. Using SnowflakeDbConnectionPool setters now throws exceptions.

  • Previously, connections that altered the database, schema, role, or warehouse (for example, by executing the ALTER SESSION SET command) parameters, were pooled. The new default behavior for such cases destroys altered connections when closing does not return them to the pool. If you want to use altered connections in the pool you need to add ChangedSession=OriginalPool to your connection string.

  • Connections with external browser authentication or, some cases of KeyPair/JWT token authentication, are no longer stored in the pool by default. To enable pooling such connections you must add poolingEnabled=true to the connection string. For other authentication methods pooling is enabled by default.

  • For more information about using connection pool, see Using Connection Pools.

• NONPOXYHOSTS parameter behavior change:

  The behavior for NONPROXYHOSTS parameter has changed. Previously a host would not be proxied if its name contained the value specified in this parameter. Now the host is not proxied when it is exactly the value specified in the parameter. For instance, previously NONPROXYHOSTS=c would match any host containing “c”, such as “your-account.snowflakecomputing.com” as well. After the change, you have to specify the whole host, such as NONPROXYHOSTS=your-account.snowflakecomputing.com, to make it non-proxied.

New features and improvements¶

• Changed connection pool behavior with multiple pools (one per each unique connection string) and connection string driven configuration. For more information about using connection pool, see Using Connection Pools.

• Targeting to .netstandard 2.0.

• Added a strong name signature to the driver assembly.

• Added ability to set the QueryTag parameter in the connection string and on the SnowflakeDbCommand object to mark the connection and command queries with a tag.

• Bumped the BouncyCastle.Cryptography dependency.

• Bumped the Google.Cloud.Storage.V1 dependency.

• Introduced a new DISABLE_SAML_URL_CHECK parameter that disables checking if the SAML postback URL matches the host URL when authenticating with Okta.

Bug fixes¶

• Fixed the handling of date and time values passed with bindings for queries with very large amount of bindings (more than CLIENT_STAGE_ARRAY_BINDING_THRESHOLD).

• Fixed sending SQL queries to the server by sending original queries instead of trimmed queries that resulted in errors for queries ending with comments.

• Implemented a more reliable way of providing hosts in NONPROXYHOSTS parameter.

• Fixed support of double quotes in DB, SCHEMA, WAREHOUSE, ROLE connection string parameters.

• Fixed S3 clients by adding “https://” to ServiceUrl if it is missing.

• Updated the secret detector to better mask secrets when logging.

• Added setting a proper SnowflakeDbParameter.DbType value.

• Fixed the logic of shortening the connectionTimeout by retryTimeout in case of an infinite retryTimeout value.

• Applied the logic of increasing maxHttpRetries to the default value for HTTP clients. Previously it was applied only to Okta authentication.

New features and improvements¶

• Added support for running asynchronous queries.

Bug fixes¶

• Improved exceptions thrown from the Okta authenticator.

• Fixed an issue with validating very short (1-2 character) account names.

• Fixed an issue related to retrieving the WAREHOUSE property from a connection string with quoted content, such as "WAREHOUSE=\"two words\"".

BCR (Behavior Change Release) changes¶

• To enhance security, the driver no longer searches a temporary directory for easy logging configurations. Additionally, the driver now requires the logging configuration file on Unix-style systems to limit file permissions to allow only the file owner to modify the files (such as chmod 0600, chmod 0644).

• The driver now throws a SnowflakeDbException with a QueryID for PUT/GET failures. Previously, the driver returned different types of exceptions, such as FileNotFound and DirectoryNotFound. If your application checked for any of these exceptions, you must update your code to handle only SnowflakeDbException for PUT/GET failures.

• The driver no longer supports older versions, such as V1 and V2, of the chunk parser/downloader. As part of the upgrade to version V3, the driver no longer supports the SFConfiguration.UseV2JsonParser or SFConfiguration.UseV2ChunkDownloader configuration options. If you used commands similar to the following, you should remove them:

  • SFConfiguration.Instance().ChunkParserVersion = 1; or SFConfiguration.Instance().ChunkParserVersion = 2;

  • SFConfiguration.Instance().ChunkDownloaderVersion = 1; or SFConfiguration.Instance().ChunkDownloaderVersion = 2;

  • SFConfiguration.Instance().UseV2JsonParser

  • SFConfiguration.Instance().UseV2ChunkDownloader

New features and improvements¶

• Added support for multiple SAML integrations.

Bug fixes¶

• Improved security in the easy logging feature, including:

  • Using a more reliable way of determining which driver directory to use when searching for client configuration files.

  • No longer using a temporary directory for configuration search.

  • Enforcing additional file permissions checks under Unix for increased security.

  • Adding more verbose logging.

• Fixed an Okta retry issue for SSO/SAML endpoints.

• Added fast failing for commands without text execution.

• Fixed exceptions thrown from PUT/GET failed executions to contain QueryId if possible.

• Replaced the Portable.BouncyCastle library with BouncyCastle.Cryptography.

BCR (Behavior Change Release) changes¶

• Beginning with version 2.2.0, the .NET driver automatically replaces underscores (_) in account names with hyphens (-) when constructing a host name based on an account name. This change impacts PrivateLink customers whose account names contain underscores. In this situation, you must override the default value by setting allowUnderscoresInHost to true. You can override this behavior by setting allowUnderscoresInHost=true in the ConnectionString.

  This change was made to fix the DNS resolution errors that occurred when connecting over the public link with Snowflake accounts that had underscores in their account names.

New features and updates¶

• Improved Arrow performance.

• Automatically replaces underscores (_) in account names with hyphens (-) when constructing a host name based on an account name.

• Added an allowUnderscoresInHost configuration parameter to allow underscores (_) in account names to be maintained in the constructed host name. This parameter lets you override the behavior change associated with this release.

Bug fixes¶

• To fix an issue with connection timeouts, the driver now closes expired sessions asynchronously when connecting.