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I have a function C++ file, created in VS 2005. But I am not sure how to register that function in mysql, so that it get stored somewhere in mysql database and when the query runs, it should retrieve the func definition from the database itself..

Please guide me with the procedure. Thanks

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A quick clarification: a C++ source file cannot be stored as “runnable source” inside MySQL and executed later by the server. There are two different ways to get function-like behavior inside MySQL: (1) write a stored function/procedure in SQL (these bodies are stored in the server’s data dictionary and can be inspected with SHOW CREATE FUNCTION/PROCEDURE), or (2) implement a loadable function (historically called a UDF) in C/C++, compile it as a shared library, and register that library with the server. These are different mechanisms and solve different problems. (dev.mysql.com)

If you need native C++ code (for performance or to reuse a C++ library), the usual flow is: build a shared library that matches your MySQL server build/OS (DLL on Windows, .so on Linux), put it where the server will load it (plugin_dir), then register it with the server so SQL can call it. Registration adds metadata (mysql.func / performance_schema user_defined_functions) rather than storing your C++ source in the database. Also: DROP the function before replacing the library when you upgrade it — otherwise the server can behave unpredictably. (docs.oracle.com)

Important cautions and alternatives: CREATE FUNCTION for loadable functions requires privileges (it writes into mysql.func), and loadable functions run inside the server process — a bad UDF can crash the server or create security risks. For modern MySQL versions, the plugin API is the preferred, safer extension mechanism; if the logic can be expressed in SQL, a stored function/procedure is simpler and safer. Replicated setups require the same library available to slaves. (docs.oracle.com)

Practical troubleshooting tips: check the server error log when a UDF fails to load; verify plugin_dir and file permissions; ensure 32/64-bit and compiler/runtime compatibility; confirm exported symbol names (and presence of required init/deinit symbols) if mysqld rejects the library. ’s Windows guide is a useful starting point for building on Visual Studio, but consult the official MySQL docs for exact requirements for your MySQL version before deploying to production. ()

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Thanks :)This really helped

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