Changes in MySQL Connector/NET 9.3.0 (2025-04-15; General Availability)$$$Functionality Added or Changed$$$Bugs Fixed$$$$$$Functionality Added or Changed$$$The following are the updated version requirements of Connector/NET on some of the third-party libraries it uses (see Connector/NET Installation for details):$$$$$$Google Protobuf .NET version 3.30.0$$$ZstdSharp version 0.8.5$$$Kerberos version 1.21.3$$$BouncyCastle version 2.5.1.$$$OpenTelemetry .NET version 1.11.2$$$(WL #16852)$$$$$$Bugs Fixed$$$The test GetSchemaReturnColumnsByOrdinalPosition() in the testsuite failed because the server has changed the precision for displaying floating values resulted from arithmatic operations. The patch fixes the test. (Bug #37705281)$$$$$$Performing a database migration using MySql.EntityFrameworkCore 9.0.0 or later resulted in a SQL syntax error. (Bug #117258; Bug #37513445)$$$$$$Timeout testing for Connector/NET used non-existing server addresses; which caused unexpected behaviors. With this fix; the tests now use mock servers instead. (WL #16033)

Changes in MySQL Connector/NET 9.2.0 (2025-01-21; General Availability)$$$Functionality Added or Changed$$$$$$Bugs Fixed$$$$$$Functionality Added or Changed$$$Added .NET 9 GA and EF Core 9 GA support; and removed .NET 6 and EF Core 6 support. (WL #16638; WL #16654)$$$$$$Bugs Fixed$$$The MySql.Data.OpenTelemetry.dll metadata reported the version as 0.0.0.0. (Bug #37198051)$$$$$$Added ROW_COUNT() concurrency checking in EFCore for update operations.$$$$$$Our thanks to Ryan Kelly for the contribution. (Bug #115853; Bug #36960454)$$$$$$The MySQLUpdateSqlGenerator class now inherits from UpdateAndSelectSqlGenerator instead of UpdateSqlGenerator.$$$$$$Our thanks to Hikari Fujioka for the contribution. (Bug #115020; Bug #36624158)$$$$$$Added a NULL check to the MySQLActivitySource class.$$$$$$Our thanks to Maximilian Bienhüls for the contribution. (Bug #114457; Bug #36568102)$$$$$$Added a new rewritebatchedstatements connection option that makes the connector rewrite batched statements and execute them all at once in a single block rather than one at a time; which is default behavior.$$$$$$Note that this connection option impacts functions like LAST_INSERT_ID().$$$$$$Our thanks to Sebastian Schwarzhuber for the contribution. (Bug #110553; Bug #35240186)

Changes in MySQL Connector/NET 9.1.0 (2024-10-15; General Availability)$$$Functionality Added or Changed$$$Bugs Fixed$$$$$$Functionality Added or Changed$$$Connector/NET now supports .NET 9 and Entity Framework Core 9 (preview versions). (WL #16308)$$$$$$The OpenTelemetry.Api library is no longer bundled; it now pulls in the OpenTelemetry.Api 1.9.0 NuGet package. (WL #16453)$$$$$$Added OpenID Connect support leveraging the new authentication_openid_connect_client client-side authentication plugin. OpenID Connect functionality is supported by MySQL Enterprise Edition Server 9.1.0 and later.$$$$$$The new OpenidIdentityToken connection option defines a path to a file containing the JWT formatted identity token. (WL #16491)$$$$$$Bugs Fixed$$$Changed EntityFramework to use the actual column name in JOIN statements to prevent clashes.$$$$$$Our thanks to Kristoffer Sjöberg for the contribution. (Bug #116028; Bug #37032982)$$$$$$Made improvements to MySqlPoolManager.GetPoolAsync related fixes that were made in Connector/NET 8.2.0.$$$$$$Our thanks to Stuart Lang for the contribution. (Bug #111759; Bug #35937318)$$$$$$References: This issue is a regression of: Bug #110717.$$$$$$Executing SELECT statements on Big-Endian client machines could cause MySQL to unexpectedly halt.$$$$$$Our thanks to Sidraya Jayagond for the contribution. (Bug #111630; Bug #35937293)

Changes in MySQL Connector/NET 9.0.0 (2024-07-01; General Availability)$$$Deprecation and Removal Notes$$$$$$Functionality Added or Changed$$$$$$Bugs Fixed$$$$$$Deprecation and Removal Notes$$$Removed the deprecated OldGetStringBehavior connection option. (WL #16280)$$$$$$Functionality Added or Changed$$$Removed .NET Core 7 and Entity Framework Core 7 support; as they received End of Support status on May 14; 2024. (WL #16386)$$$$$$Bugs Fixed$$$Improved how the connection pool releases connections. (Bug #36483069)$$$$$$The AppendReturningClause method is now overridden to prevent an DatabaseGeneratedOption.Computed attribute annotation from adding an unsupported RETURNING clause to the generated SQL.$$$$$$Our thanks to Wang Shiyao for the contribution. (Bug #113443; Bug #36116171)

Deprecation and Removal Notes$$$The deprecated authentication_fido_client authentication plugin and associated FidoActionRequested connection option was removed. Instead; use the authentication_webauthn_client authentication plugin. (WL #16150)$$$$$$Functionality Added or Changed$$$Expanded the metadata present in the MSI package and DLL files. (WL #16204)$$$$$$Added TLS 1.3 support for .NET Framework 4.6; and also enabled TLS 1.3 for .NET Framework 4.8 and .NET 6 and above. (WL #16176)$$$$$$Connector/NET is now ready to support the VECTOR data type when it becomes available with MySQL Enterprise Server. (WL #16175)$$$$$$Known limitation of this release: because the mysql_native_password authentication plugin is disabled by default as of MySQL Server 8.4.0; some unit tests may generate errors unless the plugin is enabled.$$$$$$Bugs Fixed$$$Setting MinPoolSize to a value other than 0 would throw an exception and prevent new connections. (Bug #36319784)$$$$$$Using either shared memory or a named pipe for a connection in a multithread environment would throw an exception. (Bug #36208929; Bug #36208932)$$$$$$Mapping a column to a byte array had a limit of 8000 characters; and attempting to insert a larger value would insert an empty value. (Bug #36208913)$$$$$$The pool manager could cause a deadlock to occur. Our thanks to Marek Matys for the patch. (Bug #114272; Bug #36380976)

Changes in MySQL Connector/NET 8.3.0 (2024-01-16; General Availability)$$$Deprecation and Removal Notes$$$$$$Functionality Added or Changed$$$$$$Bugs Fixed$$$$$$Deprecation and Removal Notes$$$Calling the MySqlDataReader.GetString() method now throws an InvalidCastException exception if the associated column is not a string type.$$$$$$The OldGetStringBehavior connection option was added to allow (by setting it to true) restoring previous behavior by logging a deprecation warning instead of throwing the exception. This option defaults to false.$$$$$$This option will be removed in the near future; potentially in version 9.0.0. (WL #15972)$$$$$$Functionality Added or Changed$$$Previously; each Entity Framework Core (EF Core) NuGet package supported a single .NET target. For instance; the connector’s EF Core 8 package was able to target .NET 8.0 only. Now; the package-target support relationships are:$$$$$$EF Core 6 targets .NET 6$$$$$$EF Core 7 targets .NET 6; .NET 7$$$$$$EF Core 8 targets .NET 6; .NET 7; .NET 8$$$$$$(Bug #35968775)$$$$$$Upgraded the Google.Protobuf dependency to version 3.25.1. (WL #16075)$$$$$$Previously; Connector/NET 8.2.0 supported .NET 8 and Entity Framework Core 8.0 (EF8) preview releases only. Connector/NET now supports all .NET 8 and EF8 releases. (WL #16035)$$$$$$Added Microsoft.Build.Traversal support; executing MSBUILD dirs.proj in the Connector/NET root folder now builds all projects in the repository (MySQL.Data; MySQL.Data.OpenTelemetry; MySQL.Web; EntityFramework; and EFCore) as defined in dirs.proj. (WL #15798)$$$$$$Bugs Fixed$$$Added an AssemblyInfo file for MySQL.Data.OpenTelemtry. (Bug #35957212)$$$$$$After an application called Dispose() on a connection object; it was possible to reopen the connection. Now; the connector returns an exception if an attempt is made to reopen a disposed connection. (Bug #35827809)$$$$$$The timeout period of a transaction could elapsed prior to obtaining a connection from the connection pool. This might occur because all pooled connections were neither discarded from nor returned to the pool; but remained marked as InUse. The fix resolves an issue that prevented the removal of a connection from the connection pool after an exception was thrown. (Bug #112123; Bug #35731216)

Changes in MySQL Connector/NET 8.2.0 (2023-10-25; General Availability)$$$Packaging Notes$$$$$$Functionality Added or Changed$$$$$$Bugs Fixed$$$$$$Packaging Notes$$$Updated the Portable.BouncyCastle 1.9.0 NuGet package reference to BouncyCastle.Cryptography 2.2.1; which is the currently maintained package. (Bug #111361; Bug #35488339)$$$$$$Functionality Added or Changed$$$Combined all of the Entity Framework Core projects (6; 7; and 8) into a single project under a folder named EFCore. (WL #15799)$$$$$$Connector/NET now supports .NET 8.0 and Entity Framework Core 8.0 (preview versions). (WL #15792)$$$$$$Connector/NET now supports an authentication method that enables users to authenticate to MySQL Server using WebAuthn-aware devices for classic MySQL protocol connections. WebAuthn authentication is based on the FIDO and FIDO2 standards. For an overview of the supported client-side authentication plugins and authentication methods; see Connector/NET Authentication. (WL #15193)$$$$$$Bugs Fixed$$$Applications like Microsoft Excel and Microsoft Power BI Desktop emitted an error when used with Connector/NET 8.0.33 and later. This fix identifies and restores the missing component. (Bug #110975; Bug #35379875)$$$$$$Multiple MySqlConnection objects on separate threads called simultaneously could return ArgumentException or InvalidOperationException when MySqlPoolManager.GetPoolAsync tried to modify the shared thread-pool object concurrently from the different threads. (Bug #110717; Bug #35307501)

Functionality Added or Changed$$$This release of Connector/NET upgrades the NuGet package reference for Google.Protobuf to version 3.21.9; which has been publicly reported as not vulnerable to CVE-2022-3171. (Bug #34859629)$$$$$$To enhance the performance of connections; Connector/NET now determines whether a connection string has been analyzed already before performing the analysis for a second time. (Bug #102964; Bug #32680315)$$$$$$It is now possible to pass a stream object to the MySqlBulkLoader.Load() method for copying bulk data to a database. Our thanks to Alexander Reinert for the patch. (Bug #74392; Bug #21049228)$$$$$$Connector/NET now fully supports .NET 7 and Entity Framework Core 7.0 (EF7) for applications that target .NET 7 exclusively. Previously; Connector/NET 8.0.31 supported the .NET 7 and EF7 previews.$$$$$$Bugs Fixed$$$Connector/NET could not authenticate a valid client user through Oracle Cloud Infrastructure pluggable authentication. Now; the connector implements new constraints to ensure that the client-side plugin loads the OCI.DotNetSDK.Common assembly; which contains the required functions needed to authenticate a client user. (Bug #34851463)$$$$$$When unloading the assembly; the procedure recommended by Microsoft was not performed accurately for .NET Core frameworks. Our thanks to Gabriele Gervasi for the patch. (Bug #108837; Bug #34724334)$$$$$$An unexpected System.NullReferenceException message was returned when the MySqlCommand.Cancel() method was called for a command associated with a closed (or disposed) MySqlConnection object. The issue is resolved with new validation in the method that now checks the connection state. (Bug #101507; Bug #32127591)$$$$$$Some methods of the MySqlDataReader class that should retrieve an integer value instead could return unexpected values. This behavior had multiple causes. First; the connector was not properly informed by the TreatTinyAsBoolean property that it should treat type TINYINT(1) as INT or BOOL. In addition; Connector/NET implemented the conversion to a different type inconsistently. (Bug #99091; Bug #31087580)$$$$$$When executing multiple INSERT statements in one MySQLCommand call; the LastInsertedId property was set to zero because the connector read an extra OK packet from the server that omitted LastInsertedId. Now; Connector/NET avoids overriding the value if it is set. (Bug #97061; Bug #30365157)$$$$$$Improved validation now ensures that the MySqlParameterCollection.Add() method behaves consistently when it checks whether a named parameter has been added already. (Bug #93370; Bug #28980952)$$$$$$Values of the Size; Scale; Precision; IsNullable; and SourceColumnNullMapping properties were omitted during the copy operation performed by the MySqlParameter.Clone() method. (Bug #92734; Bug #28777779)$$$$$$The MySqlException.Number property for authentication-related exceptions always returned a value of zero. (Bug #78426; Bug #21830667)$$$$$$Output parameters in combination with a command of type CommandType.Text were not supported. This fix changed how Connector/NET manages the parameters with an output direction for text commands. (Bug #75267; Bug #20259756)

Functionality Added or Changed$$$Connector/NET now provides DNS Service (SRV) records support without depending on libraries that were previously omitted from the Connector/NET 8.0.19 (and later) NuGet packages. This update does not change how the DNS-SRV feature looks up; extracts the SRV records; or uses those records to establish a connection (see Opening a Connection Using a Single DNS Domain).$$$$$$Connector/NET now supports .NET 7 (preview) and continues to support a range of frameworks (see Connector/NET Versions).$$$$$$Connector/NET now fully supports EF Core 7.0 (preview) for applications that target .NET 7 exclusively. Applications that target .NET Framework (or any .NET Standard version) cannot use this feature.$$$$$$Bugs Fixed$$$One of the links published for submitting a pull request was not well-formed. Our thanks to Adam Croot for the patch. (Bug #108290; Bug #34535732)$$$$$$NuGet was not able to display license information for Connector/NET packages accurately. Our thanks to Matthew Steeples for the patch. (Bug #108091; Bug #34477295)$$$$$$On systems running .NET 6; Connector/NET could throw an exception when trying to perform an equality check involving type Datetime.Date. (Bug #107618; Bug #34317220)$$$$$$After a connection timeout expired; exception type TimeoutException was thrown when MySqlException was expected. (Bug #107600; Bug #34299402)$$$$$$Incomplete dependencies prevented Connector/NET from installing and running properly. (Bug #107316; Bug #34189859)$$$$$$If an exception occurred during the execution of a SQL statement within a transaction; the subsequent transaction rollback produced a null reference exception; which could cause the Web server (IIS) process to halt unexpectedly. This fix changes the way the connection object manages rollback behavior. (Bug #107110; Bug #34107186)$$$$$$The overall performance of the MySql.Data.MySqlClient.MySqlParameterCollection.Add(Object) method was improved by changing the return statement. (Bug #105997; Bug #33710643)$$$$$$When a query attribute and a command parameter had the exact same name; Connector/NET overwrote the value of the attribute with the value from the parameter; which then prevented using mysql_query_attribute_string to retrieve an accurate value for the attribute. Connector/NET now removes all parameter names when sending a prepared statement. (Bug #105728; Bug #33620022)$$$$$$Additional validation now checks the MySqlParameter value assignment to ensure that binary data in a MemoryStream object can be read properly. (Bug #102593; Bug #32506736)$$$$$$An error was emitted after passing in MySqlParameter.MySqlDbType set with type MySqlDbType.Int24 to commandcuteNonQuery() using a prepared statement. (Bug #95986; Bug #29959095)$$$$$$

Bugs Fixed$$$X DevAPI: Connector/NET permitted setting a null or empty string () value to represent a document path when modifying a collection. Now; the Set() method enforces using the dollar sign character ($) as the document path argument. (Bug #34243143)$$$$$$The link to the Oracle Contributor Agreement (OCA) page specified in the CONTRIBUTING file was incorrect. (Bug #34082302)$$$$$$Connections to a properly configured server using the named-pipe transport protocol were not possible when running MySQL Server as a Windows service. (Bug #33974737)$$$$$$With the SSL mode set to VerifyCA or VerifyFull; SSL connections could not be established if the client certificates were chained. (Bug #33179908)$$$$$$The MySql.Data NuGet package was dependent on an unmaintained version of BouncyCastle. This fix replaces the dependency with Portable.BouncyCastle; which contains the BouncyCastle DLL and is current. (Bug #106370; Bug #33827732)$$$$$$The mechanism used to clean up idle connections in the connection pool performed poorly. This fix changes the idle list from type Queue<T> to type LinkedList<T> to reduce the overall number of idle connections remaining in the pool after a connection surge is over and the load requirement is reduced. (Bug #106368; Bug #33935441)$$$$$$Type MySqlDbType.Enum could not be used with the MySqlParameter method in a prepared statement. (Bug #106247; Bug #33827735)$$$$$$Previously; it was possible to cancel the MySqlConnection.OpenAsync operation if the CancellationToken object was canceled. This fix restores the original behavior. (Bug #106243; Bug #33781447)$$$$$$References: Reverted patches: Bug #28662512.$$$$$$MySqlCommand.CommandText emitted an error if the stored procedure to execute included one or more backtick characters (`) in the name. (Bug #104913; Bug #33338458)