在 Debian 9 Stretch 上安装 mysql-server 时出错（依赖问题）

Question

使用 Debian 9.5，全新安装。我想安装 mysql-server，但遇到依赖问题。

sudo apt-get install mysql-server
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 mysql-server : Depends: default-mysql-server but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

apt-get install mysql-server default-mysql-server
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 default-mysql-server : Depends: mariadb-server-10.1 but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

sudo apt-get install mysql-server default-mysql-server mariadb-server-10.1
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 mariadb-server-10.1 : Depends: libdbi-perl but it is not going to be installed
                       Recommends: libhtml-template-perl but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

sudo apt-get install mysql-server default-mysql-server mariadb-server-10.1 libhtml-template-perl
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 libhtml-template-perl : Depends: libcgi-pm-perl but it is not going to be installed or
                                  perl (< 5.19) but 5.26.2-7 is to be installed
 mariadb-server-10.1 : Depends: libdbi-perl but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

sudo apt-get install mysql-server default-mysql-server mariadb-server-10.1 libdbi-perl
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 libdbi-perl : Depends: perlapi-5.24.1
E: Unable to correct problems, you have held broken packages.

编辑1 apt-cache policy：：

apt-cache policy
Package files:
 100 /var/lib/dpkg/status
     release a=now
 500 http://security.debian.org/debian-security stretch/updates/contrib amd64 Packages
     release v=9,o=Debian,a=stable,n=stretch,l=Debian-Security,c=contrib,b=amd64
     origin security.debian.org
 500 http://security.debian.org/debian-security stretch/updates/main amd64 Packages
     release v=9,o=Debian,a=stable,n=stretch,l=Debian-Security,c=main,b=amd64
     origin security.debian.org
 500 http://deb.debian.org/debian stretch-updates/main amd64 Packages
     release o=Debian,a=stable-updates,n=stretch-updates,l=Debian,c=main,b=amd64
     origin deb.debian.org
 500 http://deb.debian.org/debian stretch/main amd64 Packages
     release v=9.5,o=Debian,a=stable,n=stretch,l=Debian,c=main,b=amd64
     origin deb.debian.org
Pinned packages:

编辑2 apt policy perl perl-base：：

apt policy perl perl-base
perl:
  Installed: 5.26.2-7
  Candidate: 5.26.2-7
  Version table:
 *** 5.26.2-7 100
        100 /var/lib/dpkg/status
     5.24.1-3+deb9u4 500
        500 http://deb.debian.org/debian stretch/main amd64 Packages
        500 http://security.debian.org/debian-security stretch/updates/main amd64 Packages
perl-base:
  Installed: 5.26.2-7
  Candidate: 5.26.2-7
  Version table:
 *** 5.26.2-7 100
        100 /var/lib/dpkg/status
     5.24.1-3+deb9u4 500
        500 http://deb.debian.org/debian stretch/main amd64 Packages
        500 http://security.debian.org/debian-security stretch/updates/main amd64 Packages

如何解决这些依赖问题？

Answer 1

正如您的apt policy perl perl-base输出所示，并由jordanm指出，您的系统具有 Perl 的 Buster 版本，而不是 Debian 9 版本。所以你的系统并不是真正的 Debian 9.5 的“全新安装”；由于 Perl 是 Debian 设置中如此重要的组件，很可能还有许多其他软件包已升级到 Buster 版本。

这种 Perl 不匹配是您无法安装 MySQL 软件包的原因。

我假设这是最近安装的，因此您没有太多投资；所以在这种情况下，jordanm建议重新安装可能是最好的解决方案。Debian 9 和 Buster 有很大不同，因此回滚可能会变得相当复杂，尤其是在您升级了 Perl 之后。删除mc肯定是不够的。

将来，不要将稳定版和测试版混在一起。如果您遇到阻止您使用包的错误，请提交错误 ( reportbug mc)；如果它足够严重，它可能有资格获得稳定的更新。你也可以要求反向移植；这将使您获得mc为 Debian 9 重建的当前 Buster 版本。