Changes in MySQL Connector/ODBC 9.4.0 (2025-07-22; General Availability)$$$Note$$$These release notes were created with the assistance of HeatWave GenAI.$$$$$$Bugs Fixed$$$.NET applications quit unexpectedly while trying to connect to a MySQL server using Connector/ODBC. This has been fixed by adding the -DISABLE_CONSTEXPR_MUTEX_CONSTRUCTOR option when compiling Connector/ODBC and the mysqlclient library. (Bug #37845086)$$$$$$The commercial Debian package installed some of the documentation files under the wrong folders. Those files are now put under ./usr/share/doc/mysql-connector-odbc-commercial/ as expected. (Bug #37771319)$$$$$$Company name and other pieces of information were missing when the Connector/ODBC DLLs were examined by; for example; choosing its Properties in the Windows Explorer and looking at the Details tab. (Bug #37199170)$$$$$$A memory leak occurred when there was an error with my_pos_update(). This has been fixed now by proper error handing and statement deallocations. (Bug #18532085)$$$$$$

Changes in MySQL Connector/ODBC 9.3.0 (2025-04-15; General Availability)$$$Functionality Added or Changed$$$$$$Bugs Fixed$$$$$$Functionality Added or Changed$$$All instances of the deprecated function mysql_real_escape_string() in the source code have been replaced by an internal implementation of myodbc_escape_string(); which works similarly and can also handle the escaping of wildcard characters (_ and %) in LIKE expressions. (Bug #116559; Bug #37250400)$$$$$$The following Connector/ODBC Connection Parameters can now be configured on the ODBC administrator GUI:$$$$$$readtimeout$$$$$$writetimeout$$$$$$OPENTELEMETRY$$$$$$(WL #16587)$$$$$$Bugs Fixed$$$The MSI installer checked for the wrong version of Visual C++ Redistributable required by Connector/ODBC when installing it on a system. With this fix; it now requires the system to have version 14.40 or higher of the Visual C++ Redistributable 2022. (Bug #37536382)$$$$$$Reported errors that occurred while executing multiple statements with a single query were generic and without context. For example; SQLMoreResults might return unhandled error from mysql_next_result() instead of the error reported by MySQL Server. (Bug #37423741)$$$$$$References: This issue is a regression of: Bug #49466; Bug #11757423.$$$$$$On macOS; Connector/ODBC failed to create connections to servers for accounts that required pluggable authentication. It was due to faulty links to the 3rd-party libraries bundled with Connector/Python; which were corrected by this patch. (Bug #37090584)$$$$$$An assertion failure occurred unnecessarily when SQLBindCol() attempted to bind data to column 0 without bookmarks being enabled. (Bug #18641803)$$$$$$Memory leaks occur with the SQLCancel() function; because it failed to free the MYSQL* handle in the case of a failed connection. (Bug #18534345)$$$$$$When using server-side prepared statements; fetching a time column bound to the SQL_C_CHAR type returned an incorrect string if the hour value had 3 digits. (Bug #116087; Bug #37071646)$$$$$$If the SQLCloseCursor() method was called when no result set was available; no error was returned. With this patch; the method returned SQL State: 24000 and the error message Invalid cursor state in the situation. (Bug #72311; Bug #26474326)

Changes in MySQL Connector/ODBC 9.3.0 (2025-04-15; General Availability)$$$Functionality Added or Changed$$$$$$Bugs Fixed$$$$$$Functionality Added or Changed$$$All instances of the deprecated function mysql_real_escape_string() in the source code have been replaced by an internal implementation of myodbc_escape_string(); which works similarly and can also handle the escaping of wildcard characters (_ and %) in LIKE expressions. (Bug #116559; Bug #37250400)$$$$$$The following Connector/ODBC Connection Parameters can now be configured on the ODBC administrator GUI:$$$$$$readtimeout$$$$$$writetimeout$$$$$$OPENTELEMETRY$$$$$$(WL #16587)$$$$$$Bugs Fixed$$$The MSI installer checked for the wrong version of Visual C++ Redistributable required by Connector/ODBC when installing it on a system. With this fix; it now requires the system to have version 14.40 or higher of the Visual C++ Redistributable 2022. (Bug #37536382)$$$$$$Reported errors that occurred while executing multiple statements with a single query were generic and without context. For example; SQLMoreResults might return unhandled error from mysql_next_result() instead of the error reported by MySQL Server. (Bug #37423741)$$$$$$References: This issue is a regression of: Bug #49466; Bug #11757423.$$$$$$On macOS; Connector/ODBC failed to create connections to servers for accounts that required pluggable authentication. It was due to faulty links to the 3rd-party libraries bundled with Connector/Python; which were corrected by this patch. (Bug #37090584)$$$$$$An assertion failure occurred unnecessarily when SQLBindCol() attempted to bind data to column 0 without bookmarks being enabled. (Bug #18641803)$$$$$$Memory leaks occur with the SQLCancel() function; because it failed to free the MYSQL* handle in the case of a failed connection. (Bug #18534345)$$$$$$When using server-side prepared statements; fetching a time column bound to the SQL_C_CHAR type returned an incorrect string if the hour value had 3 digits. (Bug #116087; Bug #37071646)$$$$$$If the SQLCloseCursor() method was called when no result set was available; no error was returned. With this patch; the method returned SQL State: 24000 and the error message Invalid cursor state in the situation. (Bug #72311; Bug #26474326)

Changes in MySQL Connector/ODBC 9.2.0 (2025-01-21; General Availability)$$$$$$Functionality Added or Changed$$$$$$Added a new WEBAUTHN_DEVICE_NUMBER connection option that is passed to and interpreted by the WebAuthN authentication plugin. It accepts a numeric value that selects the authenticator device to use during WebAuthN authentication. Previously; the first (#0) authentication plugin was always used. (WL #16646)$$$$$$Bugs Fixed$$$The user defined traceparent query attribute in an OpenTelemetry instrumented application was not sent to the server; which resulted in user (or connector) generated OpenTelemetry spans to not associate with the corresponding server spans. (Bug #37188732)$$$$$$References: This issue is a regression of: Bug #36841317.$$$$$$Retrieving a list of records that contained an empty BLOB field could return an unexpected result. (Bug #116657; Bug #37286526)$$$$$$For fixed column types; such as CHAR; having these fields contain unexpected multi-byte characters could cause a returned data that does not match expected data length for column error.$$$$$$The connector now enables the PAD_CHAR_TO_FULL_LENGTH sql_mode. (Bug #114470; Bug #37298936)$$$$$$Improved result set handling produced by catalog functions. When SQLFreeStmt() with SQL_UNBIND or SQL_RESET_PARAMS was called after a catalog function (such as SQLProcedureColumns); the result set produced by the catalog function was not cleared in accordance to ODBC API requirements for unbinding result columns and resetting parameters. (Bug #109466; Bug #36906892)

hanges in MySQL Connector/ODBC 9.1.0 (2024-10-15; General Availability)$$$Functionality Added or Changed$$$$$$Bugs Fixed$$$$$$Functionality Added or Changed$$$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.$$$$$$The new openid-token-file connection option defines a path to a file containing the JWT formatted identity token. (WL #16436)$$$$$$The RPM and DEB packages now install a copy of the MySQL client library plugins for the connector. The version of these plugins match the version of the statically linked MySQL client library.$$$$$$They are installed to {libdir}/mysql/libmyodbc{ABI}/plugin/ where {libdir} is the system location where packages install libraries. {ABI} is the connectors ABI version; which is currently 9.$$$$$$The connector installed from RPM and DEB packages use the bundled plugins as needed without requiring the PLUGIN_DIR connection option; although the PLUGIN_DIR connection option is still available to change the plugin location. Runtime dependencies required by the plugins; such as Kerberos and LDAP libraries; are expected on the system and installed from their own packages. (WL #16457)$$$$$$Bugs Fixed$$$The Generic Linux TGZ package did not bundle all client-side authentication plugins. (Bug #36972449)$$$$$$Fixed a potential Out of Bounds (OOB) issue related to escaping large queries. (Bug #36955942)$$$$$$Added a plugin caching mechanism. (Bug #36929669)$$$$$$Fixed a memory leak that occurred when emitting SQL_DATE errors. (Bug #18531881)$$$$$$The internal mysql_init() function used for making connections is now thread safe. (Bug #115710; Bug #36894687)$$$$$$Having a number of bound parameters greater than the number of placeholders in the corresponding SQL query could emit an error; as the statement had to be prepared and executed more than once. (Bug #115584; Bug #36841317)$$$$$$When connected to a MySQL 5.7 server; queries using bound parameters would not succeed and emitted a No data supplied for parameters in prepared statement error. (Bug #115531; Bug #36828312)$$$$$$With the prefetch connection option set to a non-zero value; large queries could cause the connector to unexpectedly halt. (Bug #113554; Bug #36945554)$$$$$$Fixed the SQLBulkOperations() functions generated WHERE clause; which could potentially cause an application to unexpectedly halt. (Bug #69194; Bug #18641963; Bug #26474373)

Changes in MySQL Connector/ODBC 9.0.0 (2024-07-01; General Availability)$$$Functionality Added or Changed$$$$$$Bugs Fixed$$$$$$Functionality Added or Changed$$$For the ANSI driver; converting to and from the character set specified by the CHARSET connection option is now performed by the MySQL server rather than being done inside the ANSI driver. (WL #16297)$$$$$$Added support for the VECTOR data type that was introduced in MySQL Enterprise Server 9.0.0. (WL #16171)$$$$$$The charset connection option is now deprecated for the Unicode driver; and setting it to a non-empty value via SQLConnect() or SQLDriverConnect() emits a warning. The connection is still successful. (WL #16311)$$$$$$As of this release; the base name of the driver modules is changed to myodbc9. (WL #16382)$$$$$$Bugs Fixed$$$On Windows; the MSI installation location now defaults to C:\Program Files\MySQL\MySQL Connector ODBC X.Y instead of C:\Program Files\MySQL\Connector ODBC X.Y where X.Y is the series number; such as 9.0. This change aligns MySQL Connector/ODBC with other MySQL products. (Bug #36681453)$$$$$$Since 8.2.0; the SQLConnect() functions parameter values did not override values defined in the DSN. Now the SQLConnect() values are prioritized except for SQLConnect() values defined as NULL. (Bug #36605973)

Changes in MySQL Connector/ODBC 8.4.0 (2024-04-30; General Availability)$$$Security Notes$$$$$$Functionality Added or Changed$$$$$$Bugs Fixed$$$$$$Security Notes$$$For platforms on which Connector/ODBC utilizes MySQL Servers bundled OpenSSL library (MacOS; Windows; and GenLinux); MySQL Servers linked OpenSSL library was updated to version 3.0.13. Issues fixed in OpenSSL version 3.0.13 are described at https://www.openssl.org/news/cl30.txt. (Bug #36278301)$$$$$$Functionality Added or Changed$$$Expanded the Windows file attributes for packaged executable and DLL files. (Bug #113544; Bug #36153794; WL #16157)$$$$$$Removed support for the deprecated authentication_fido authentication plugin. Instead; use authentication_webauthn. (WL #16155)$$$$$$Setting query attributes for executed queries now supports prepared statements in SSPS mode. (WL #15967)$$$$$$Known limitation of this release: because the mysql_native_password authentication plugin is disabled by default as of MySQL Server 8.4.0; some unit tests may generate errors unless the plugin is enabled.$$$$$$Bugs Fixed$$$Unchecking the Disable schema support (NO_SCHEMA) option in the ODBC connection editor would remove (unset) the value rather than set it to 0; which meant that reloading the ODBC connector editor would revert it to the default value of 1. Now both NO_SCHEMA and NO_CATALOG are always set to either 0 or 1. (Bug #36238361)$$$$$$Fixed build errors to adhere to the C99 standard; which GCC 14 now enforces.$$$$$$Our thanks to Christopher Fore for this contribution. (Bug #113766; Bug #36228848)$$$$$$Not all packaged files contained digital signatures. (Bug #113538; Bug #36150212)$$$$$$Could not execute parameterized stored procedures using syntax that contained curly brackets. (Bug #112285; Bug #35790175)$$$$$$Changing position in the row set with SQLSetPos() would not update the lengths; which could cause SQLGetData() to retrieve less data than expected. (Bug #61991; Bug #26474471)

Changes in MySQL Connector/ODBC 8.3.0 (2024-01-16; General Availability)$$$Functionality Added or Changed$$$$$$Bugs Fixed$$$$$$Functionality Added or Changed$$$The AUTO_RECONNECT functionality was removed; and setting it returns SQL_SUCCESS_WITH_INFO with an HY000 error stating that its no longer supported. The GUI dialog removed the AUTO_RECONNECT option while the myodbc-installer command-line tool allows setting it but emits a warning.$$$$$$MySQL Server 8.3.0 removed auto-reconnect support after deprecating it in versions 8.0.34 and 8.1.0. (WL #15978)$$$$$$Improved OpenTelemetry support to propagate context when executing prepared statements. (WL #15960)$$$$$$Bugs Fixed$$$ADODB.Recordset.Open() reported a transaction error when a string type was used with prepared statements. The fix was changing the SQL_MAX_CONCURRENT_ACTIVITIES value from 1 to 0 (unlimited). (Bug #36031548)$$$$$$References: This issue is a regression of: Bug #34916959.$$$$$$