mysql2 gem 安装失败，依赖项未满足：libmysqlclient-dev

Question

我遇到了与 this poster on the askubuntu forums. I've started with a clean Ubuntu 14.04 install several times now and keep getting the same error no matter what I do 类似的问题。

The following packages have unmet dependencies:
 libmysqlclient-dev : Depends: libmysqlclient18 (= 5.5.46-0ubuntu0.14.04.2) but 10.0.23+maria-1~trusty is to be installed
E: Unable to correct problems, you have held broken packages.

重现错误：

已按照 MariaDB site 上 10.0 版的说明进行操作。我在之前的尝试中也尝试过 10.1。

我的服务器上安装了 Ruby (2.2.3) on Rails (4.2.5)。设置我的应用程序，配置 Gemfile 和 bundle install

An error occurred while installing mysql2 (0.4.2), and Bundler cannot continue.
    Make sure that `gem install mysql2 -v '0.4.2'` succeeds before bundling.

然后我 gem install mysql2 -v '0.4.2' 得到以下内容：

mysql client is missing. You may need to 'apt-get install libmysqlclient-dev' or 'yum install mysql-devel', and try again.

所以我 apt-get install libmysqlclient-dev 并得到错误 Unable to correct problems, you have held broken packages，如本 post 的第一部分所示。

信息：

apt-cache policy libmysqlclient18 & 

 libmysqlclient18:
  Installed: 10.0.23+maria-1~trusty
  Candidate: 10.0.23+maria-1~trusty
  Version table:
 *** 10.0.23+maria-1~trusty 0
        500 http://sfo1.mirrors.digitalocean.com/mariadb/repo/10.0/ubuntu/ trusty/main amd64 Packages
        100 /var/lib/dpkg/status
     5.5.46-0ubuntu0.14.04.2 0
        500 http://mirrors.digitalocean.com/ubuntu/ trusty-updates/main amd64 Packages
        500 http://security.ubuntu.com/ubuntu/ trusty-security/main amd64 Packages
     5.5.35+dfsg-1ubuntu1 0
        500 http://mirrors.digitalocean.com/ubuntu/ trusty/main amd64 Packages

我缺少哪一步可以使捆绑包安装不会遇到 mysql2 gem 的问题（并且仍然使用 MariaDB）？ mysql -uroot -p 从终端运行正常。

Answer 1

purge 所有 mysql 相关包

sudo apt-get remove --purge mysql*
sudo apt-get autoremove
sudo apt-get autoclean
sudo apt-get update

现在，您有了一个干净的系统。再次尝试安装 mariadb

sudo apt-get install mariadb-server libmariadbclient-dev mariadb-client mysql-common  libmysqlclient18 libmariadbd-dev

只需确保提示您安装的软件包版本与本页给出的版本相同： http://ftp.yz.yamagata-u.ac.jp/pub/dbms/mariadb/repo/10.0/ubuntu/pool/main/m/mariadb-10.0/

否则，它会从 Ubuntu 的官方仓库安装 Mysql 包，这将导致 conflict.If 发生，您应该设置 maria db 仓库更高的优先级，如这一页： https://askubuntu.com/questions/293619/assign-higher-priority-to-ppa

希望对你有帮助

mysql2 gem 安装失败，依赖项未满足：libmysqlclient-dev

mysql2 gem install fails with unmet dependencies: libmysqlclient-dev

mysql

ubuntu

ruby-on-rails

mariadb