我在启动Ruby on Rails项目时遇到了问题

Question

I'm starting a new project but I have issues installing sqlite3 on my computer. What is the problem?

Building native extensions. This could take a while...
ERROR:  Error installing sqlite3:
        ERROR: Failed to build gem native extension.

    current directory: C:/Ruby26-x64/lib/ruby/gems/2.6.0/gems/sqlite3-1.4.0/ext/sqlite3
C:/Ruby26-x64/bin/ruby.exe -I C:/Ruby26-x64/lib/ruby/2.6.0 -r ./siteconf20190428-9612-10i9sod.rb extconf.rb
checking for sqlite3.h... yes
checking for pthread_create() in -lpthread... yes
checking for -ldl... no
checking for dlopen()... no
missing function dlopen
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of necessary
libraries and/or headers.  Check the mkmf.log file for more details.  You may
need configuration options.

I have already installed Ruby, Rails, Bundle. But apparently, something is missing.

Answer 1

I had this error on my win7, and this was my solution:

type ridk exec pacman -S mingw-w64-x86_64-dlfcn and install

This should work if your install ruby in 'common' way. Like 'rubyinstaller'.

Answer 2

You can consider skipping SQLite altogether. The only reason Rails is setup for SQLite by default is that its easy to setup up on most systems. If not then its mostly a waste of time.

Its not really a viable option for deployment as its file based. This is especially if you want to deploy to cloud platforms such as Heroku which use ephemeral file systems.

You will want to develop and test on the same database that you are going to deploy to such as Postgres.

Differences between backing services mean that tiny incompatibilities crop up, causing code that worked and passed tests in development or staging to fail in production. These types of errors create friction that disincentivizes continuous deployment. The cost of this friction and the subsequent dampening of continuous deployment is extremely high when considered in aggregate over the lifetime of an application.

• https://12factor.net/dev-prod-parity