Rails安装mysql - 安装mysql2出错：ERROR: 无法构建本地扩展宝石。

Question

我有一个使用 Rails 3.2.13 的应用程序需要部署，但是托管服务需要使用 MySQL，而不是我一直在使用的 sqlite。

在从 sqlite 转换到 MySQL 的过程中，我必须安装 ruby gem mysql2，但是在安装过程中出现了以下错误：

Error installing mysql2: ERROR: Failed to build gem native extension.

我已经尝试了 bundle install 和 gem install mysql2，但是都出现了相同的错误消息。

我知道许多人使用的解决方案是 sudo apt-get install libmysql-ruby libmysqlclient-dev，但是我正在 Windows 上使用 Git Bash，因此我找到了一个适用于 Windows 的等价方法（该问题的 @francois 答案 this question）。我使用安装程序安装了 MySQL Server 5.6 并运行了以下命令：

gem install mysql2 -- '--with-mysql-lib="c:\Program Files\MySQL\MySQL Server 5.6\lib" --with-mysql-include="c:\Program Files\MySQL\MySQL Server 5.6\include"' 

根据我所阅读的，这应该成功安装'mysql2' ruby gem。但是奇怪的是，我仍然遇到了以下错误：

    Temporarily enhancing PATH to include DevKit... Building native extensions with: '--with-mysql-lib="c:\Program

Files\MySQL\MySQL Server 5.6\lib" --with-mysql-include="c:\Program Files\MySQL\MySQL Server 5.6\i nclude"' This could take a while... ERROR: Error installing mysql2: ERROR: Failed to build gem native extension.

        c:/RailsInstaller/Ruby1.9.3/bin/ruby.exe extconf.rb --with-mysql-lib="c:\Pro gram Files\MySQL\MySQL Server 5.6\lib" --with-mysql-include="c:\Program Files\My SQL\MySQL Server 5.6\include" checking for rb_thread_blocking_region()... yes checking for rb_wait_for_single_fd()... yes checking for rb_hash_dup()... yes

checking for rb_intern3()... yes checking for main() in -llibmysql... yes checking for mysql.h... yes checking for errmsg.h... yes checking for mysqld_error.h... yes creating Makefile

    make generating mysql2-i386-mingw32.def compiling client.c client.c: In function 'rb_raise_mysql2_error': client.c:139:3:

warning: ISO C90 forbids mixed declarations and code client.c: In function 'finish_and_mark_inactive': client.c:508:3: warning: ISO C90 forbids mixed declarations and code client.c: In function 'rb_mysql_client_abandon_results': client.c:535:3: warning: ISO C90 forbids mixed declarations and code client.c: In function 'rb_mysql_client_next_result': client.c:938:5: warning: ISO C90 forbids mixed declarations and code compiling mysql2_ext.c compiling result.c result.c: In function 'rb_mysql_result_fetch_fields': result.c:407:35: warning: comparison between signed and unsigned integer express ions linking shared-object mysql2/mysql2.so client.o: In function nogvl_connect': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:158: undefined reference tomysql_real_connect@32' client.o: In function nogvl_init': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:150: undefined reference tomysql_init@4' client.o: In function set_ssl_options': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:1078: undefined reference tomysql_ssl_set@24' client.o: In function mysql_client_options': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:723: undefined reference tomysql_options@12' c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:727: undefined reference to mysql_error@4' client.o: In functionrb_mysql_info': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:267: undefined reference to mysql_info@4' client.o: In functionrb_mysql_client_warning_count': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:257: undefined reference to mysql_warning_count@4' client.o: In functionnogvl_do_result': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:370: undefined reference to mysql_store_result@4' client.o: In functionrb_mysql_client_more_results': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:923: undefined reference to mysql_more_results@4' client.o: In functionnogvl_select_db': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:863: undefined reference to mysql_select_db@8' client.o: In functionnogvl_ping': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:894: undefined reference to mysql_ping@4' client.o: In functionrb_mysql_client_thread_id': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:856: undefined reference to mysql_thread_id@4' client.o: In functionrb_mysql_client_last_id': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:825: undefined reference to mysql_insert_id@4' client.o: In functionnogvl_read_query_result': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:357: undefined reference to mysql_read_query_result@4' client.o: In functionrb_mysql_client_server_info': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:788: undefined reference to mysql_get_server_version@4' c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:789: undefined reference tomysql_get_server_info@4' client.o: In function rb_mysql_client_info': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:756: undefined reference tomysql_get_client_version@0' c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:757: undefined reference to mysql_get_client_info@0' client.o: In functionrb_mysql_client_real_escape': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:662: undefined reference to mysql_real_escape_string@16' client.o: In functionfinish_and_mark_inactive': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:515: undefined reference to mysql_free_result@4' client.o: In functionnogvl_send_query': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:334: undefined reference to mysql_send_query@12' client.o: In functionnogvl_close': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:190: undefined reference to mysql_close@4' client.o: In functionrb_mysql_client_escape': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:238: undefined reference to mysql_escape_string@12' client.o: In functionrb_raise_mysql2_error': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:125: undefined reference to mysql_error@4' c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:126: undefined reference tomysql_sqlstate@4' c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:140: undefined reference to mysql_errno@4' client.o: In functionrb_connect': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:297: undefined reference to mysql_errno@4' client.o: In functionrb_mysql_client_store_result': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:966: undefined reference to mysql_errno@4' client.o: In functionrb_mysql_client_next_result': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:939: undefined reference to mysql_next_result@4' client.o: In functionrb_mysql_client_affected_rows': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:839: undefined reference to mysql_affected_rows@4' client.o: In functionrb_mysql_client_async_result': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:419: undefined reference to mysql_errno@4' client.o: In functionrb_mysql_client_abandon_results': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:539: undefined reference to mysql_next_result@4' c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:538: undefined reference tomysql_more_results@4' c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:547: undefined reference to mysql_free_result@4' client.o: In functionnogvl_do_result': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:368: undefined reference to mysql_use_result@4' client.o: In functionnogvl_close': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:190: undefined reference to mysql_close@4' client.o: In functionset_charset_name': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:1067: undefined reference to mysql_options@12' c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:1069: undefined reference tomysql_error@4' client.o: In function init_mysql2_client': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/cl ient.c:1105: undefined reference tomysql_get_client_info@0' result.o: In function rb_mysql_result_count': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/re sult.c:576: undefined reference tomysql_num_rows@4' result.o: In function rb_mysql_result_fetch_field': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/re sult.c:126: undefined reference tomysql_fetch_field_direct@8' c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/re sult.c:114: undefined reference to mysql_num_fields@4' result.o: In functionrb_mysql_result_fetch_fields': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/re sult.c:403: undefined reference to mysql_num_fields@4' result.o: In functionnogvl_fetch_row': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/re sult.c:105: undefined reference to mysql_fetch_row@4' result.o: In functionrb_mysql_result_free_result': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/re sult.c:75: undefined reference to mysql_free_result@4' result.o: In functionrb_mysql_result_fetch_row': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/re sult.c:213: undefined reference to mysql_fetch_lengths@4' c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/re sult.c:215: undefined reference tomysql_num_fields@4' result.o: In function rb_mysql_result_each': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/re sult.c:503: undefined reference tomysql_fetch_fields@4' result.o: In function rb_mysql_result_free_result': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/re sult.c:75: undefined reference tomysql_free_result@4' result.o: In function rb_mysql_result_each': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/re sult.c:531: undefined reference tomysql_fetch_fields@4' result.o: In function rb_mysql_result_free_result': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/re sult.c:75: undefined reference tomysql_free_result@4' result.o: In function rb_mysql_result_each': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/re sult.c:490: undefined reference tomysql_num_rows@4' result.o: In function rb_mysql_result_free_result': c:\RailsInstaller\Ruby1.9.3\lib\ruby\gems\1.9.1\gems\mysql2-0.3.13\ext\mysql2/re sult.c:75: undefined reference tomysql_free_result@4' collect2: ld returned 1 exit status make: *** [mysql2.so] Error 1

    Gem files will remain installed in c:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9 .1/gems/mysql2-0.3.13

for inspection. Results logged to c:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/mysql2-0. 3.13/ext/mysql2/gem_make.out

Can anyone please help?  I am having much trouble comprehending what's wrong with the installation.

- jytoronto

Answer 1

我在Win64环境中遇到了相同的错误。

我尝试了很多解决方案，但唯一有效的是：

• gem install mysql2 -v '0.3.11'

- mariomol

---

谢谢你！你救了我！！ - writeToBhuwan

谢谢，我已经尝试了所有的方法！ - Will

Answer 2

我一直被同一个问题困扰，最终成功安装了mysql2。感谢odiszapc@github。我发现谷歌上除下面这个解决方案以外的其他方法对我都不起作用。

这段话是从这里复制粘贴来的，所以不归功于我。

gem uninstall mysql2

Download last MySQL connector from http://cdn.mysql.com/Downloads/Connector-C/mysql-    connector-c-noinstall-6.0.2-win32.zip

Extract it to C:\connector-6.0.2

gem install mysql2 --platform=ruby -- '--with-mysql-lib="C:\connector-6.0.2\lib" --with-mysql-include="C:\connector-6.0.2\include" --with-mysql-dir="C:\connector-6.0.2"'

我的附加信息。

• ruby 1.9.3p392 (2013-02-22) [i386-mingw32]
• Rails 3.2.13
• MySQL Server 5.6
• mysql2-0.3.13

附注： 即使您成功安装了mysql2，您可能仍然需要一些工作（例如mysql2.so（LoadError）），这与我的情况有关，并且似乎是关于mysql2的又一个重大故障。

- Quv

---

我不得不删除一些库和包含选项，因为它抱怨找不到它们...很奇怪...对于我来说，命令是：gem install mysql2 --platform=ruby -- '--with-mysql-dir="C:\connector-6.0.2"' - Mark Murphy

Answer 3

我正在安装在Windows 7 64位上。 对我有用的是：

从以下链接下载32位C连接器压缩包：http://dev.mysql.com/downloads/connector/c/

我将其提取到C：\ Temp。 如果您使用不同的目录，请调整下一个命令。

gem install mysql2 --platform=ruby -- '--with-mysql-dir="C:\Temp\mysql-connector-c-6.1.3-win32"'

- jim

Answer 4

痛苦...很多痛苦。最终做到了：

（平台：Windows64位，Ruby32位，DevKit32位...）

1. 从http://dev.mysql.com/get/Downloads/Connector-C/mysql-connector-c-noinstall-6.0.2-win32.zip/from/pick下载C语言的mysql连接器。
2. 将连接器解压缩到一个没有空格的目录中！
3. 将lib/libmysql.dll文件复制到ruby/bin目录中。
4. gem install mysql2 -- --with-mysql-dir=D:\RoR\mysql-connector-c（因此提供连接器的目录而不是服务器的目录）。

然后我成功地运行了mysql2 v0.3.17...

- Alfredo

Answer 5

1. 从http://dev.mysql.com/get/Downloads/Connector-C/mysql-connector-c-noinstall-6.0.2-win32.zip/from/pick下载Mysql连接器。
2. 解压它。复制lib\libmysql.dll文件并将其粘贴到Ruby的bin目录中，例如：C:\RailsInstaller\Ruby1.9.3\bin
3. 现在重新安装Mysql2 gem
   gem install mysql2 -- '--with-mysql-lib="c:\Program Files\MySQL\MySQL Server 5.0\lib\opt" --with-mysql-include="c:\Program Files\MySQL\MySQL Server 5.0\include"'
   注意：根据您的情况更改mysql安装路径
   
4. 尝试捆绑(bundle)吧

- Radhakrishna