曾以為Windows版本的mysql存在不能使用UDF的BUG諸提交了一個bug報告。不過似乎發現是我搞錯了，MySQL的技術支持人員給了非常完美的解答，同大家分享一下。下邊是原文回復。 用戶你好。抱歉，這並不是一個bug。下面我粘貼一個以前為某個客戶做的簡例，假設你有了VC++,源碼分發，並且有一個正常運行的MySQL服務器。 我將創建一個UDF它將一個名字: 注意:例子非常簡陋，目的是讓你了解該如何處理手頭的UDF。 - 打開 mysqld.dsw 工作區。 - 添加新項目到這個工作區 - Project name: my_udf // 項目名稱:my_udf - 選擇 Win32 Dynamic-Link Library // Win32動態連接庫 - 點擊 OK - 選擇 An Empty DLL project // 一個空DLL項目 - 點擊 Finish - 點擊 OK - 添加新文件 my_udf.cpp 到項目中: #include #include #include extern "C" { char *my_name(UDF_INIT *initid, UDF_ARGS *args, char *is_null, char *error); // 兼容C } char *my_name(UDF_INIT *initid, UDF_ARGS *args, char *is_null, char *error) { char * me = "my name"; return me; // 調用此UDF將返回 my name } - 按 Ctrl+N 來創建一個新文件。 - 選擇 text 類型 - File name: my_udf.def file://文件名:my_udf.def - 按照下邊的內容編輯文件。 LIBRARY UDF_EXAMPLE DESCRIPTION 'Example Using UDF with VC++' VERSION 1.0 EXPORTS my_name - 右擊my_udf項目並選擇Settings - 點 C/C++ 選項卡 - 選擇 General - 添加宏 HAVE_DLOPE 到預處理器定義 - 選擇 Preprocessor - 添加頭文件路徑: Additional Include Directories 例如: ../include - 按 F7 去編譯成 DLL. - 復制 my_udf.dll 到環境變量path定義過的目錄 比如 \winnt\system32 。 - 打開mysql客戶端 C:\mysql-udf\bin>mysql -uroot -p Enter passWord: Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 2 to server version: 3.23.52-max-nt Type 'help;' or '\h' for help. Type '\c' to clear the buffer. mysql> CREATE FUNCTION my_name RETURNS STRING SONAME "my_udf.dll"; Query OK, 0 rows affected (0.08 sec) mysql> select my_name(); mysql> drop function my_name; Query OK, 0 rows affected (0.00 sec) 以下是MySQL技術人員的回信原文： Sorry this isn't a bug. Below I pasted a sample I did sometime ago for another user: Ok. Assuming you have VC++ and the source distribution and a server running, I will create a UDF that returns a name: Note: the sample is ugly, but the purpose here is to show you how to handle the UDF. - Open the mysqld.dsw workspace. - Add New project to the workspace - Project name: my_udf - Select Win32 Dynamic-Link Library - Click OK - Select An Empty DLL project - Click Finish - Click OK - Add a new file called my_udf.cpp to the project: #include #include #include extern "C" { char *my_name(UDF_INIT *initid, UDF_ARGS *args, char *is_null, char *error); } char *my_name(UDF_INIT *initid, UDF_ARGS *args, char *is_null, char *error) { char * me = "my name"; return me; } - Type Ctrl+N for to create a new file. - Select text type - File name: my_udf.def - Edit the above file with the below contents: LIBRARY UDF_EXAMPLE DESCRIPTION 'Example Using UDF with VC++' VERSION 1.0 EXPORTS my_name - Right Click the my_udf project and select Settings - Click the C/C++ tab - Select General in the Category Combo - Add the macro HAVE_DLOPEN to the PreProcessor definition - Select Preprocessor in the Category Combo - Add the include path to the text box: Additional Include directories e.g: ../include - Press F7 for to build the DLL. - Copy the my_udf.dll to the environment path directory: \winnt\system32 for example. - Start the mysql client and issue: C:\mysql-udf\bin>mysql -uroot -p Enter password: Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 2 to server version: 3.23.52-max-nt Type 'help;' or '\h' for help. Type '\c' to clear the buffer. mysql> CREATE FUNCTION my_name RETURNS STRING SONAME "my_udf.dll"; Query OK, 0 rows affected (0.08 sec) mysql> select my_name(); mysql> drop function my_name; Query OK, 0 rows affected (0.00 sec)
