Changes in MySQL Connector/C++ 8.0.12 (2018-07-27, General Availability)

• Installation Notes

• Packaging Notes

• Security Notes

• X DevAPI Notes

• Bugs Fixed

Installation Notes

• Because the Microsoft Visual C++ 2017 Redistributable installer deletes the Microsoft Visual C++ 2015 Redistributable registry keys that identify its installation, standalone MySQL MSIs may fail to detect the Microsoft Visual C++ 2015 Redistributable if both it and the Microsoft Visual C++ 2017 Redistributable are installed. The solution is to repair the Microsoft Visual C++ 2017 Redistributable via the Windows Control Panel to recreate the registry keys needed for the runtime detection. Unlike the standalone MSIs, MySQL Installer for Windows contains a workaround for the detection problem. (Bug #28345281, Bug #91542)

Packaging Notes

• An RPM package for installing ARM 64-bit (aarch64) binaries of Connector/C++ on Oracle Linux 7 is now available in the MySQL Yum Repository and for direct download.

  Known Limitation for this ARM release: You must enable the Oracle Linux 7 Software Collections Repository (ol7_software_collections) to install this package, and must also adjust the libstdc++7 path. See Yum's Platform Specific Notes for additional details.

• Installers for Connector/C++ are now available in these formats: MSI packages (Windows); RPM packages (Linux); DMG packages (macOS). See Installing Connector/C++ from a Binary Distribution. (WL #11670, WL #11671, WL #11672)

Security Notes

• yaSSL is no longer included in Connector/C++ source distributions. wolfSSL may be used as a functionally equivalent alternative that has a GPLv2-compatible license. In addition, wolfSSL (like OpenSSL) supports the TLSv1.2 protocol, which yaSSL does not.

  To build Connector/C++ using wolfSSL, use the -DWITH_SSL=path_name CMake option, where path_name indicates the location of the wolfSSL sources. For more information, see Source Installation System Prerequisites, and Connector/C++ Source-Configuration Options. (WL #11683)

X DevAPI Notes

• Connector/C++ now supports NOWAIT and SKIP LOCKED lock contention modes to be used with lockExclusive() and lockShared() clauses of CRUD find/select operations (see Locking Read Concurrency with NOWAIT and SKIP LOCKED), and a default lock contention mode. The following list names the permitted constants. For each item, the first and second constants apply to X DevAPI and X DevAPI for C, respectively.

  • LockContention::DEFAULT, LOCK_CONTENTION_DEFAULT: Block the query until existing row locks are released.

  • LockContention::NOWAIT, LOCK_CONTENTION_NOWAIT: Return an error if the lock cannot be obtained immediately.

  • LockContention::SKIP_LOCKED, LOCK_CONTENTION_SKIP_LOCKED: Execute the query immediately, excluding from the query items that are locked.

  For X DevAPI and X DevAPI for C applications, lock mode methods accept these lock contention constants as a parameter. For X DevAPI applications, lock mode methods can be called without this parameter, as before; this is equivalent to passing a lock mode of DEFAULT.

  For more information, see Working with Locking. (WL #11374)

• Connector/C++ now supports the SHA256_MEMORY authentication mechanism for connections using the X Protocol. For X DevAPI applications, SessionOption::AUTH supports the new value AuthMethod::SHA256_MEMORY. For X DevAPI for C applications, the session option MYSQLX_OPT_AUTH supports the new value MYSQLX_AUTH_SHA256_MEMORY. These new values request using the sha256_memory authentication mechanism when creating a session. (WL #11685)

• To increase compliance with the X DevAPI, these Connector/C++ changes were made:

  • getAffectedItemsCount() was moved from Result to Result_common.

  • Collection.modify(condition).arrayDelete() was removed.

  • getAffectedRowsCount() was removed. Use getAffectedItemsCount() instead.

  • getWarningCount() was renamed to getWarningsCount().

Bugs Fixed

• utf8mb4 character data was handled incorrectly. (Bug #28240202)

• Session creation had a memory leak. (Bug #27917942)

• When configuring to build Connector/C++ with the legacy connector, CMake did not account for the MYSQL_CONFIG_EXECUTABLE option. (Bug #27874173, Bug #90389)

• Improper error handling for unknown hosts when creating a session could result in unexpected application exit. (Bug #27868302)

• The mysqlx_row_fetch_one() X DevAPI for C function could fail to return for large result set exceeding the maximum packet size. Now such result sets produce an error. (Bug #27732224)